diff --git a/pkg/analysis_server/doc/api.html b/pkg/analysis_server/doc/api.html
index 5423376..be632ea 100644
--- a/pkg/analysis_server/doc/api.html
+++ b/pkg/analysis_server/doc/api.html
@@ -973,7 +973,8 @@
         </p>
         <p>
           If a package root is a file, then the analyzer
-          will behave as though that file is a ".packages" file in the
+          will behave as though that file is a
+          ".dart_tool/package_config.json" file in the
           source directory. The effect is the same as specifying the file
           as a "--packages" parameter to the Dart VM when
           executing any Dart file inside the source directory.
diff --git a/pkg/analysis_server/lib/protocol/protocol_generated.dart b/pkg/analysis_server/lib/protocol/protocol_generated.dart
index d5a90a6..dc2c12a 100644
--- a/pkg/analysis_server/lib/protocol/protocol_generated.dart
+++ b/pkg/analysis_server/lib/protocol/protocol_generated.dart
@@ -2583,9 +2583,9 @@
   /// the normal package: URI resolution mechanism.
   ///
   /// If a package root is a file, then the analyzer will behave as though that
-  /// file is a ".packages" file in the source directory. The effect is the
-  /// same as specifying the file as a "--packages" parameter to the Dart VM
-  /// when executing any Dart file inside the source directory.
+  /// file is a ".dart_tool/package_config.json" file in the source directory.
+  /// The effect is the same as specifying the file as a "--packages" parameter
+  /// to the Dart VM when executing any Dart file inside the source directory.
   ///
   /// Files in any directories that are not overridden by this mapping have
   /// their package: URI's resolved using the normal pubspec.yaml mechanism. If
diff --git a/pkg/analysis_server/test/integration/support/integration_test_methods.dart b/pkg/analysis_server/test/integration/support/integration_test_methods.dart
index fddcbfa..bf671b2 100644
--- a/pkg/analysis_server/test/integration/support/integration_test_methods.dart
+++ b/pkg/analysis_server/test/integration/support/integration_test_methods.dart
@@ -500,9 +500,10 @@
   ///   the normal package: URI resolution mechanism.
   ///
   ///   If a package root is a file, then the analyzer will behave as though
-  ///   that file is a ".packages" file in the source directory. The effect is
-  ///   the same as specifying the file as a "--packages" parameter to the Dart
-  ///   VM when executing any Dart file inside the source directory.
+  ///   that file is a ".dart_tool/package_config.json" file in the source
+  ///   directory. The effect is the same as specifying the file as a
+  ///   "--packages" parameter to the Dart VM when executing any Dart file
+  ///   inside the source directory.
   ///
   ///   Files in any directories that are not overridden by this mapping have
   ///   their package: URI's resolved using the normal pubspec.yaml mechanism.
diff --git a/pkg/analysis_server/tool/spec/generated/java/AnalysisServer.java b/pkg/analysis_server/tool/spec/generated/java/AnalysisServer.java
index 59da953..d2dda69 100644
--- a/pkg/analysis_server/tool/spec/generated/java/AnalysisServer.java
+++ b/pkg/analysis_server/tool/spec/generated/java/AnalysisServer.java
@@ -216,12 +216,12 @@
    *         not be analyzed.
    * @param packageRoots A mapping from source directories to package roots that should override the
    *         normal package: URI resolution mechanism. If a package root is a file, then the analyzer
-   *         will behave as though that file is a ".packages" file in the source directory. The
-   *         effect is the same as specifying the file as a "--packages" parameter to the Dart VM
-   *         when executing any Dart file inside the source directory. Files in any directories that
-   *         are not overridden by this mapping have their package: URI's resolved using the normal
-   *         pubspec.yaml mechanism. If this field is absent, or the empty map is specified, that
-   *         indicates that the normal pubspec.yaml mechanism should always be used.
+   *         will behave as though that file is a ".dart_tool/package_config.json" file in the source
+   *         directory. The effect is the same as specifying the file as a "--packages" parameter to
+   *         the Dart VM when executing any Dart file inside the source directory. Files in any
+   *         directories that are not overridden by this mapping have their package: URI's resolved
+   *         using the normal pubspec.yaml mechanism. If this field is absent, or the empty map is
+   *         specified, that indicates that the normal pubspec.yaml mechanism should always be used.
    */
   public void analysis_setAnalysisRoots(List<String> included, List<String> excluded, Map<String, String> packageRoots);
 
diff --git a/pkg/analysis_server/tool/spec/spec_input.html b/pkg/analysis_server/tool/spec/spec_input.html
index 1d7b96a..5c07676 100644
--- a/pkg/analysis_server/tool/spec/spec_input.html
+++ b/pkg/analysis_server/tool/spec/spec_input.html
@@ -870,7 +870,8 @@
         </p>
         <p>
           If a package root is a file, then the analyzer
-          will behave as though that file is a ".packages" file in the
+          will behave as though that file is a
+          ".dart_tool/package_config.json" file in the
           source directory. The effect is the same as specifying the file
           as a "--packages" parameter to the Dart VM when
           executing any Dart file inside the source directory.
diff --git a/pkg/analysis_server_client/lib/src/protocol/protocol_generated.dart b/pkg/analysis_server_client/lib/src/protocol/protocol_generated.dart
index 484915e..58d9f35 100644
--- a/pkg/analysis_server_client/lib/src/protocol/protocol_generated.dart
+++ b/pkg/analysis_server_client/lib/src/protocol/protocol_generated.dart
@@ -2583,9 +2583,9 @@
   /// the normal package: URI resolution mechanism.
   ///
   /// If a package root is a file, then the analyzer will behave as though that
-  /// file is a ".packages" file in the source directory. The effect is the
-  /// same as specifying the file as a "--packages" parameter to the Dart VM
-  /// when executing any Dart file inside the source directory.
+  /// file is a ".dart_tool/package_config.json" file in the source directory.
+  /// The effect is the same as specifying the file as a "--packages" parameter
+  /// to the Dart VM when executing any Dart file inside the source directory.
   ///
   /// Files in any directories that are not overridden by this mapping have
   /// their package: URI's resolved using the normal pubspec.yaml mechanism. If
diff --git a/pkg/analyzer/lib/src/dart/analysis/experiments.g.dart b/pkg/analyzer/lib/src/dart/analysis/experiments.g.dart
index ee40393..ca06838 100644
--- a/pkg/analyzer/lib/src/dart/analysis/experiments.g.dart
+++ b/pkg/analyzer/lib/src/dart/analysis/experiments.g.dart
@@ -147,7 +147,7 @@
     isExpired: IsExpired.enhanced_enums,
     documentation: 'Enhanced Enums',
     experimentalReleaseVersion: null,
-    releaseVersion: null,
+    releaseVersion: Version.parse('2.17.0'),
   );
 
   static final extension_methods = ExperimentalFeature(
@@ -198,7 +198,7 @@
     isExpired: IsExpired.named_arguments_anywhere,
     documentation: 'Named Arguments Anywhere',
     experimentalReleaseVersion: null,
-    releaseVersion: null,
+    releaseVersion: Version.parse('2.17.0'),
   );
 
   static final non_nullable = ExperimentalFeature(
@@ -248,7 +248,7 @@
     isExpired: IsExpired.super_parameters,
     documentation: 'Super-Initializer Parameters',
     experimentalReleaseVersion: null,
-    releaseVersion: null,
+    releaseVersion: Version.parse('2.17.0'),
   );
 
   static final test_experiment = ExperimentalFeature(
@@ -309,7 +309,7 @@
   static const bool control_flow_collections = true;
 
   /// Default state of the experiment "enhanced-enums"
-  static const bool enhanced_enums = false;
+  static const bool enhanced_enums = true;
 
   /// Default state of the experiment "extension-methods"
   static const bool extension_methods = true;
@@ -324,7 +324,7 @@
   static const bool macros = false;
 
   /// Default state of the experiment "named-arguments-anywhere"
-  static const bool named_arguments_anywhere = false;
+  static const bool named_arguments_anywhere = true;
 
   /// Default state of the experiment "non-nullable"
   static const bool non_nullable = true;
@@ -339,7 +339,7 @@
   static const bool spread_collections = true;
 
   /// Default state of the experiment "super-parameters"
-  static const bool super_parameters = false;
+  static const bool super_parameters = true;
 
   /// Default state of the experiment "test-experiment"
   static const bool test_experiment = false;
diff --git a/pkg/analyzer/lib/src/dart/ast/ast.dart b/pkg/analyzer/lib/src/dart/ast/ast.dart
index 506e0d0..b033bbe 100644
--- a/pkg/analyzer/lib/src/dart/ast/ast.dart
+++ b/pkg/analyzer/lib/src/dart/ast/ast.dart
@@ -7686,6 +7686,7 @@
     ..addNode('target', target)
     ..addToken('operator', operator)
     ..addNode('methodName', methodName)
+    ..addNode('typeArguments', typeArguments)
     ..addNode('argumentList', argumentList);
 
   @override
diff --git a/pkg/analyzer/test/src/summary/resynthesize_common.dart b/pkg/analyzer/test/src/summary/resynthesize_common.dart
index b1c1f02..26542c5 100644
--- a/pkg/analyzer/test/src/summary/resynthesize_common.dart
+++ b/pkg/analyzer/test/src/summary/resynthesize_common.dart
@@ -12526,6 +12526,16 @@
               token: f @28
               staticElement: self::@function::f
               staticType: T Function<T>(T)
+            typeArguments: TypeArgumentList
+              leftBracket: < @29
+              arguments
+                NamedType
+                  name: SimpleIdentifier
+                    token: int @30
+                    staticElement: dart:core::@class::int
+                    staticType: null
+                  type: int
+              rightBracket: > @33
             argumentList: ArgumentList
               leftParenthesis: ( @34
               arguments
diff --git a/pkg/front_end/lib/src/api_prototype/experimental_flags_generated.dart b/pkg/front_end/lib/src/api_prototype/experimental_flags_generated.dart
index 1a8f894..953dfa4 100644
--- a/pkg/front_end/lib/src/api_prototype/experimental_flags_generated.dart
+++ b/pkg/front_end/lib/src/api_prototype/experimental_flags_generated.dart
@@ -106,17 +106,17 @@
   ExperimentalFlag.constantUpdate2018: true,
   ExperimentalFlag.constructorTearoffs: true,
   ExperimentalFlag.controlFlowCollections: true,
-  ExperimentalFlag.enhancedEnums: false,
+  ExperimentalFlag.enhancedEnums: true,
   ExperimentalFlag.extensionMethods: true,
   ExperimentalFlag.extensionTypes: false,
   ExperimentalFlag.genericMetadata: true,
   ExperimentalFlag.macros: false,
-  ExperimentalFlag.namedArgumentsAnywhere: false,
+  ExperimentalFlag.namedArgumentsAnywhere: true,
   ExperimentalFlag.nonNullable: true,
   ExperimentalFlag.nonfunctionTypeAliases: true,
   ExperimentalFlag.setLiterals: true,
   ExperimentalFlag.spreadCollections: true,
-  ExperimentalFlag.superParameters: false,
+  ExperimentalFlag.superParameters: true,
   ExperimentalFlag.testExperiment: false,
   ExperimentalFlag.tripleShift: true,
   ExperimentalFlag.valueClass: false,
diff --git a/pkg/front_end/lib/src/fasta/fasta_codes_cfe_generated.dart b/pkg/front_end/lib/src/fasta/fasta_codes_cfe_generated.dart
index 66e0e85..f786f84 100644
--- a/pkg/front_end/lib/src/fasta/fasta_codes_cfe_generated.dart
+++ b/pkg/front_end/lib/src/fasta/fasta_codes_cfe_generated.dart
@@ -4113,6 +4113,42 @@
 
 // DO NOT EDIT. THIS FILE IS GENERATED. SEE TOP OF FILE.
 const Template<
+        Message Function(
+            DartType _type, String name, bool isNonNullableByDefault)>
+    templateOptionalSuperParameterWithoutInitializer = const Template<
+            Message Function(
+                DartType _type, String name, bool isNonNullableByDefault)>(
+        problemMessageTemplate:
+            r"""Type '#type' of the optional super-initializer parameter '#name' doesn't allow 'null', but the parameter doesn't have a default value, and the default value can't be copied from the corresponding parameter of the super constructor.""",
+        withArguments: _withArgumentsOptionalSuperParameterWithoutInitializer);
+
+// DO NOT EDIT. THIS FILE IS GENERATED. SEE TOP OF FILE.
+const Code<
+        Message Function(
+            DartType _type, String name, bool isNonNullableByDefault)>
+    codeOptionalSuperParameterWithoutInitializer = const Code<
+        Message Function(
+            DartType _type, String name, bool isNonNullableByDefault)>(
+  "OptionalSuperParameterWithoutInitializer",
+);
+
+// DO NOT EDIT. THIS FILE IS GENERATED. SEE TOP OF FILE.
+Message _withArgumentsOptionalSuperParameterWithoutInitializer(
+    DartType _type, String name, bool isNonNullableByDefault) {
+  TypeLabeler labeler = new TypeLabeler(isNonNullableByDefault);
+  List<Object> typeParts = labeler.labelType(_type);
+  if (name.isEmpty) throw 'No name provided';
+  name = demangleMixinApplicationName(name);
+  String type = typeParts.join();
+  return new Message(codeOptionalSuperParameterWithoutInitializer,
+      problemMessage:
+          """Type '${type}' of the optional super-initializer parameter '${name}' doesn't allow 'null', but the parameter doesn't have a default value, and the default value can't be copied from the corresponding parameter of the super constructor.""" +
+              labeler.originMessages,
+      arguments: {'type': _type, 'name': name});
+}
+
+// DO NOT EDIT. THIS FILE IS GENERATED. SEE TOP OF FILE.
+const Template<
         Message Function(String name, String name2, DartType _type,
             DartType _type2, String name3, bool isNonNullableByDefault)>
     templateOverrideTypeMismatchParameter = const Template<
diff --git a/pkg/front_end/lib/src/fasta/kernel/body_builder.dart b/pkg/front_end/lib/src/fasta/kernel/body_builder.dart
index 5d7f537..9471504 100644
--- a/pkg/front_end/lib/src/fasta/kernel/body_builder.dart
+++ b/pkg/front_end/lib/src/fasta/kernel/body_builder.dart
@@ -1965,8 +1965,10 @@
             constructor.function.positionalParameters[0].name == "index" &&
             constructor.function.positionalParameters[1].name == "name");
         (positionalArguments ??= <Expression>[]).insertAll(0, [
-          new VariableGet(constructor.function.positionalParameters[0]),
-          new VariableGet(constructor.function.positionalParameters[1])
+          new VariableGetImpl(constructor.function.positionalParameters[0],
+              forNullGuardedAccess: false),
+          new VariableGetImpl(constructor.function.positionalParameters[1],
+              forNullGuardedAccess: false)
         ]);
       }
       if (positionalArguments != null || namedArguments != null) {
@@ -1997,7 +1999,14 @@
         initializer = buildSuperInitializer(
             true, superTarget, arguments, builder.charOffset);
       }
-      constructor.initializers.add(initializer);
+      if (libraryBuilder.enableSuperParametersInLibrary) {
+        InitializerInferenceResult inferenceResult =
+            typeInferrer.inferInitializer(this, initializer);
+        builder.addInitializer(initializer, this,
+            inferenceResult: inferenceResult);
+      } else {
+        constructor.initializers.add(initializer);
+      }
     }
     setParents(constructor.initializers, constructor);
     libraryBuilder.loader.transformListPostInference(constructor.initializers,
diff --git a/pkg/front_end/lib/src/fasta/kernel/constructor_tearoff_lowering.dart b/pkg/front_end/lib/src/fasta/kernel/constructor_tearoff_lowering.dart
index f456a4d..3b70084 100644
--- a/pkg/front_end/lib/src/fasta/kernel/constructor_tearoff_lowering.dart
+++ b/pkg/front_end/lib/src/fasta/kernel/constructor_tearoff_lowering.dart
@@ -5,6 +5,7 @@
 import 'package:kernel/ast.dart';
 import 'package:kernel/type_algebra.dart';
 
+import '../builder/library_builder.dart';
 import '../source/source_library_builder.dart';
 import '../source/source_member_builder.dart';
 import 'kernel_helper.dart';
@@ -279,7 +280,8 @@
     Procedure tearOff,
     Member target,
     List<DartType> typeArguments,
-    FreshTypeParameters freshTypeParameters) {
+    FreshTypeParameters freshTypeParameters,
+    LibraryBuilder libraryBuilder) {
   int fileOffset = tearOff.fileOffset;
 
   List<TypeParameter> typeParameters;
@@ -318,7 +320,7 @@
   _createTearOffBody(tearOff, target, arguments);
   return new SynthesizedFunctionNode(
       substitutionMap, target.function!, tearOff.function,
-      identicalSignatures: false);
+      identicalSignatures: false, libraryBuilder: libraryBuilder);
 }
 
 /// Creates the synthesized [Procedure] node for a tear off lowering by the
diff --git a/pkg/front_end/lib/src/fasta/kernel/kernel_helper.dart b/pkg/front_end/lib/src/fasta/kernel/kernel_helper.dart
index 635fec7..bd652d3 100644
--- a/pkg/front_end/lib/src/fasta/kernel/kernel_helper.dart
+++ b/pkg/front_end/lib/src/fasta/kernel/kernel_helper.dart
@@ -7,6 +7,10 @@
 import 'package:kernel/ast.dart';
 import 'package:kernel/clone.dart' show CloneVisitorNotMembers;
 import 'package:kernel/type_algebra.dart' show Substitution;
+import 'package:kernel/type_environment.dart';
+
+import '../builder/library_builder.dart';
+import '../messages.dart';
 
 /// Data for clone default values for synthesized function nodes once the
 /// original default values have been computed.
@@ -35,20 +39,26 @@
   /// named parameters.
   final bool identicalSignatures;
 
-  final List<int>? _positionalSuperParameters;
+  final List<int?>? _positionalSuperParameters;
 
   final List<String>? _namedSuperParameters;
 
   bool isOutlineNode;
 
+  final LibraryBuilder _libraryBuilder;
+
+  CloneVisitorNotMembers? _cloner;
+
   SynthesizedFunctionNode(
       this._typeSubstitution, this._original, this._synthesized,
       {this.identicalSignatures: true,
-      List<int>? positionalSuperParameters: null,
+      List<int?>? positionalSuperParameters: null,
       List<String>? namedSuperParameters: null,
-      this.isOutlineNode: false})
+      this.isOutlineNode: false,
+      required LibraryBuilder libraryBuilder})
       : _positionalSuperParameters = positionalSuperParameters,
         _namedSuperParameters = namedSuperParameters,
+        _libraryBuilder = libraryBuilder,
         // Check that [positionalSuperParameters] and [namedSuperParameters] are
         // provided or omitted together.
         assert((positionalSuperParameters == null) ==
@@ -56,11 +66,18 @@
         assert(positionalSuperParameters == null ||
             () {
               // Check that [positionalSuperParameters] is sorted if it's
-              // provided.
-              for (int i = 1; i < positionalSuperParameters.length; i++) {
-                if (positionalSuperParameters[i] <
-                    positionalSuperParameters[i - 1]) {
-                  return false;
+              // provided. The `null` values are allowed in-between the sorted
+              // values.
+              for (int i = -1, j = 0;
+                  j < positionalSuperParameters.length;
+                  j++) {
+                int? currentValue = positionalSuperParameters[j];
+                if (currentValue != null) {
+                  if (i == -1 || positionalSuperParameters[i]! < currentValue) {
+                    i = j;
+                  } else {
+                    return false;
+                  }
                 }
               }
               return true;
@@ -82,23 +99,11 @@
               return superParameterIndex == namedSuperParameters.length;
             }());
 
-  void cloneDefaultValues() {
+  void cloneDefaultValues(TypeEnvironment typeEnvironment) {
     // TODO(ahe): It is unclear if it is legal to use type variables in
     // default values, but Fasta is currently allowing it, and the VM
     // accepts it. If it isn't legal, the we can speed this up by using a
     // single cloner without substitution.
-    CloneVisitorNotMembers? cloner;
-
-    void cloneInitializer(VariableDeclaration originalParameter,
-        VariableDeclaration clonedParameter) {
-      if (originalParameter.initializer != null) {
-        cloner ??=
-            new CloneVisitorNotMembers(typeSubstitution: _typeSubstitution);
-        clonedParameter.initializer = cloner!
-            .clone(originalParameter.initializer!)
-          ..parent = clonedParameter;
-      }
-    }
 
     // For mixin application constructors, the argument count is the same, but
     // for redirecting tear off lowerings, the argument count of the tear off
@@ -109,14 +114,21 @@
       assert(_positionalSuperParameters != null ||
           _synthesized.positionalParameters.length ==
               _original.positionalParameters.length);
-      List<int>? positionalSuperParameters = _positionalSuperParameters;
+      List<int?>? positionalSuperParameters = _positionalSuperParameters;
       for (int i = 0; i < _original.positionalParameters.length; i++) {
         if (positionalSuperParameters == null) {
-          cloneInitializer(_original.positionalParameters[i],
+          _cloneInitializer(_original.positionalParameters[i],
               _synthesized.positionalParameters[i]);
         } else if (i < positionalSuperParameters.length) {
-          cloneInitializer(_original.positionalParameters[i],
-              _synthesized.positionalParameters[positionalSuperParameters[i]]);
+          int? superParameterIndex = positionalSuperParameters[i];
+          if (superParameterIndex != null) {
+            VariableDeclaration originalParameter =
+                _original.positionalParameters[i];
+            VariableDeclaration synthesizedParameter =
+                _synthesized.positionalParameters[superParameterIndex];
+            _cloneDefaultValueForSuperParameters(
+                originalParameter, synthesizedParameter, typeEnvironment);
+          }
         }
       }
 
@@ -131,7 +143,7 @@
       }
       for (int i = 0; i < _synthesized.namedParameters.length; i++) {
         if (namedSuperParameters == null) {
-          cloneInitializer(
+          _cloneInitializer(
               _original.namedParameters[i], _synthesized.namedParameters[i]);
         } else if (superParameterNameIndex < namedSuperParameters.length &&
             namedSuperParameters[superParameterNameIndex] ==
@@ -141,9 +153,12 @@
           int? originalNamedParameterIndex =
               originalNamedParameterIndices[superParameterName];
           if (originalNamedParameterIndex != null) {
-            cloneInitializer(
-                _original.namedParameters[originalNamedParameterIndex],
-                _synthesized.namedParameters[i]);
+            VariableDeclaration originalParameter =
+                _original.namedParameters[originalNamedParameterIndex];
+            VariableDeclaration synthesizedParameter =
+                _synthesized.namedParameters[i];
+            _cloneDefaultValueForSuperParameters(
+                originalParameter, synthesizedParameter, typeEnvironment);
           } else {
             // TODO(cstefantsova): Handle the erroneous case of missing names.
           }
@@ -155,7 +170,7 @@
         VariableDeclaration synthesizedParameter =
             _synthesized.positionalParameters[i];
         if (i < _original.positionalParameters.length) {
-          cloneInitializer(
+          _cloneInitializer(
               _original.positionalParameters[i], synthesizedParameter);
         } else {
           // Error case: use `null` as initializer.
@@ -175,7 +190,7 @@
           VariableDeclaration? originalParameter =
               originalParameters[synthesizedParameter.name!];
           if (originalParameter != null) {
-            cloneInitializer(originalParameter, synthesizedParameter);
+            _cloneInitializer(originalParameter, synthesizedParameter);
           } else {
             // Error case: use `null` as initializer.
             synthesizedParameter.initializer = new NullLiteral()
@@ -186,6 +201,43 @@
     }
   }
 
+  void _cloneInitializer(VariableDeclaration originalParameter,
+      VariableDeclaration clonedParameter) {
+    if (originalParameter.initializer != null) {
+      CloneVisitorNotMembers cloner = _cloner ??=
+          new CloneVisitorNotMembers(typeSubstitution: _typeSubstitution);
+      clonedParameter.initializer = cloner.clone(originalParameter.initializer!)
+        ..parent = clonedParameter;
+    }
+  }
+
+  void _cloneDefaultValueForSuperParameters(
+      VariableDeclaration originalParameter,
+      VariableDeclaration synthesizedParameter,
+      TypeEnvironment typeEnvironment) {
+    Member member = _synthesized.parent as Member;
+    Expression? originalParameterInitializer = originalParameter.initializer;
+    DartType? originalParameterInitializerType = originalParameterInitializer
+        ?.getStaticType(new StaticTypeContext(member, typeEnvironment));
+    DartType synthesizedParameterType = synthesizedParameter.type;
+    if (originalParameterInitializerType != null &&
+        typeEnvironment.isSubtypeOf(originalParameterInitializerType,
+            synthesizedParameterType, SubtypeCheckMode.withNullabilities)) {
+      _cloneInitializer(originalParameter, synthesizedParameter);
+    } else {
+      if (synthesizedParameterType.isPotentiallyNonNullable) {
+        _libraryBuilder.addProblem(
+            templateOptionalSuperParameterWithoutInitializer.withArguments(
+                synthesizedParameter.type,
+                synthesizedParameter.name!,
+                _libraryBuilder.isNonNullableByDefault),
+            synthesizedParameter.fileOffset,
+            synthesizedParameter.name?.length ?? 1,
+            _libraryBuilder.fileUri);
+      }
+    }
+  }
+
   @override
   String toString() {
     return "SynthesizedFunctionNode(original=${_original.parent}, "
diff --git a/pkg/front_end/lib/src/fasta/kernel/kernel_target.dart b/pkg/front_end/lib/src/fasta/kernel/kernel_target.dart
index 342dd2c..730ab5747 100644
--- a/pkg/front_end/lib/src/fasta/kernel/kernel_target.dart
+++ b/pkg/front_end/lib/src/fasta/kernel/kernel_target.dart
@@ -1086,7 +1086,8 @@
         superConstructor, new Arguments(positional, named: named));
     SynthesizedFunctionNode synthesizedFunctionNode =
         new SynthesizedFunctionNode(
-            substitutionMap, superConstructor.function, function);
+            substitutionMap, superConstructor.function, function,
+            libraryBuilder: classBuilder.library);
     if (!isConst) {
       // For constant constructors default values are computed and cloned part
       // of the outline expression and therefore passed to the
@@ -1144,7 +1145,7 @@
     for (SynthesizedFunctionNode synthesizedFunctionNode
         in synthesizedFunctionNodes) {
       if (!forOutline || synthesizedFunctionNode.isOutlineNode) {
-        synthesizedFunctionNode.cloneDefaultValues();
+        synthesizedFunctionNode.cloneDefaultValues(loader.typeEnvironment);
       }
     }
     if (!forOutline) {
diff --git a/pkg/front_end/lib/src/fasta/source/source_constructor_builder.dart b/pkg/front_end/lib/src/fasta/source/source_constructor_builder.dart
index f41c3b9..06f77cb 100644
--- a/pkg/front_end/lib/src/fasta/source/source_constructor_builder.dart
+++ b/pkg/front_end/lib/src/fasta/source/source_constructor_builder.dart
@@ -213,6 +213,9 @@
             (formal.isInitializingFormal || formal.isSuperInitializingFormal)) {
           formal.variable!.type = const UnknownType();
           needsInference = true;
+        } else if (!formal.hasDeclaredInitializer &&
+            formal.isSuperInitializingFormal) {
+          needsInference = true;
         }
       }
       if (needsInference) {
@@ -228,7 +231,7 @@
   }
 
   /// Infers the types of any untyped initializing formals.
-  void inferFormalTypes(ClassHierarchy classHierarchy) {
+  void inferFormalTypes(TypeEnvironment typeEnvironment) {
     if (_hasFormalsInferred) return;
     if (formals != null) {
       for (FormalParameterBuilder formal in formals!) {
@@ -250,7 +253,7 @@
               doFinishConstructor: false);
         }
         finalizeSuperInitializingFormals(
-            classHierarchy, _superParameterDefaultValueCloners, initializers);
+            typeEnvironment, _superParameterDefaultValueCloners, initializers);
       }
     }
     _hasFormalsInferred = true;
@@ -305,7 +308,7 @@
   }
 
   void finalizeSuperInitializingFormals(
-      ClassHierarchy classHierarchy,
+      TypeEnvironment typeEnvironment,
       List<SynthesizedFunctionNode> synthesizedFunctionNodes,
       List<Initializer>? initializers) {
     if (formals == null) return;
@@ -348,20 +351,20 @@
     }
 
     if (superTargetBuilder is DeclaredSourceConstructorBuilder) {
-      superTargetBuilder.inferFormalTypes(classHierarchy);
+      superTargetBuilder.inferFormalTypes(typeEnvironment);
     } else if (superTargetBuilder is SyntheticSourceConstructorBuilder) {
       MemberBuilder? superTargetOriginBuilder = superTargetBuilder.actualOrigin;
       if (superTargetOriginBuilder is DeclaredSourceConstructorBuilder) {
-        superTargetOriginBuilder.inferFormalTypes(classHierarchy);
+        superTargetOriginBuilder.inferFormalTypes(typeEnvironment);
       }
     }
 
     int superInitializingFormalIndex = -1;
-    List<int>? positionalSuperParameters;
+    List<int?>? positionalSuperParameters;
     List<String>? namedSuperParameters;
 
-    Supertype? supertype = classHierarchy.getClassAsInstanceOf(
-        classBuilder.cls, superTarget.enclosingClass);
+    Supertype? supertype = typeEnvironment.hierarchy
+        .getClassAsInstanceOf(classBuilder.cls, superTarget.enclosingClass);
     assert(supertype != null);
     Map<TypeParameter, DartType> substitution =
         new Map<TypeParameter, DartType>.fromIterables(
@@ -381,8 +384,10 @@
                 superFormals[superInitializingFormalIndex];
             formal.hasDeclaredInitializer = hasImmediatelyDeclaredInitializer ||
                 correspondingSuperFormal.hasDeclaredInitializer;
-            if (!hasImmediatelyDeclaredInitializer) {
-              (positionalSuperParameters ??= <int>[]).add(formalIndex);
+            if (!hasImmediatelyDeclaredInitializer && !formal.isRequired) {
+              (positionalSuperParameters ??= <int?>[]).add(formalIndex);
+            } else {
+              (positionalSuperParameters ??= <int?>[]).add(null);
             }
           } else {
             // TODO(cstefantsova): Report an error.
@@ -398,7 +403,7 @@
           if (correspondingSuperFormal != null) {
             formal.hasDeclaredInitializer = hasImmediatelyDeclaredInitializer ||
                 correspondingSuperFormal.hasDeclaredInitializer;
-            if (!hasImmediatelyDeclaredInitializer) {
+            if (!hasImmediatelyDeclaredInitializer && !formal.isNamedRequired) {
               (namedSuperParameters ??= <String>[]).add(formal.name);
             }
           } else {
@@ -412,8 +417,6 @@
             type = substitute(type, substitution);
           }
           formal.variable!.type = type ?? const DynamicType();
-        } else {
-          formal.variable!.type = const DynamicType();
         }
       }
     }
@@ -423,7 +426,8 @@
           substitution, superTarget.function, constructor.function,
           positionalSuperParameters: positionalSuperParameters ?? const <int>[],
           namedSuperParameters: namedSuperParameters ?? const <String>[],
-          isOutlineNode: true));
+          isOutlineNode: true,
+          libraryBuilder: library));
     }
   }
 
@@ -485,6 +489,7 @@
       superTargetBuilder
           .addSuperParameterDefaultValueCloners(synthesizedFunctionNodes);
     }
+
     synthesizedFunctionNodes.addAll(_superParameterDefaultValueCloners);
     _superParameterDefaultValueCloners.clear();
   }
diff --git a/pkg/front_end/lib/src/fasta/source/source_factory_builder.dart b/pkg/front_end/lib/src/fasta/source/source_factory_builder.dart
index 0f94bdb..16072e5 100644
--- a/pkg/front_end/lib/src/fasta/source/source_factory_builder.dart
+++ b/pkg/front_end/lib/src/fasta/source/source_factory_builder.dart
@@ -463,7 +463,8 @@
           _factoryTearOff!,
           target!,
           typeArguments ?? [],
-          _tearOffTypeParameters!));
+          _tearOffTypeParameters!,
+          library));
     }
     if (isConst && isPatch) {
       _finishPatch();
diff --git a/pkg/front_end/lib/src/fasta/source/source_type_alias_builder.dart b/pkg/front_end/lib/src/fasta/source/source_type_alias_builder.dart
index 7ff533d..b932aa9 100644
--- a/pkg/front_end/lib/src/fasta/source/source_type_alias_builder.dart
+++ b/pkg/front_end/lib/src/fasta/source/source_type_alias_builder.dart
@@ -279,7 +279,8 @@
           new Map<TypeParameter, DartType>.fromIterables(
               target.enclosingClass!.typeParameters, targetType.typeArguments),
           target.function!,
-          tearOff.function));
+          tearOff.function,
+          libraryBuilder: library));
     });
   }
 
diff --git a/pkg/front_end/lib/src/fasta/type_inference/type_inference_engine.dart b/pkg/front_end/lib/src/fasta/type_inference/type_inference_engine.dart
index d4ffcab..3459623 100644
--- a/pkg/front_end/lib/src/fasta/type_inference/type_inference_engine.dart
+++ b/pkg/front_end/lib/src/fasta/type_inference/type_inference_engine.dart
@@ -145,7 +145,7 @@
     // Field types have all been inferred so we don't need to guard against
     // cyclic dependency.
     for (DeclaredSourceConstructorBuilder builder in toBeInferred.values) {
-      builder.inferFormalTypes(classHierarchy);
+      builder.inferFormalTypes(typeSchemaEnvironment);
     }
     toBeInferred.clear();
     for (TypeDependency typeDependency in typeDependencies.values) {
diff --git a/pkg/front_end/lib/src/fasta/type_inference/type_inferrer.dart b/pkg/front_end/lib/src/fasta/type_inference/type_inferrer.dart
index 935763f..9f5f948 100644
--- a/pkg/front_end/lib/src/fasta/type_inference/type_inferrer.dart
+++ b/pkg/front_end/lib/src/fasta/type_inference/type_inferrer.dart
@@ -412,7 +412,7 @@
     } else if ((constructor = engine.toBeInferred[target]) != null) {
       engine.toBeInferred.remove(target);
       engine.beingInferred[target] = constructor!;
-      constructor.inferFormalTypes(classHierarchy);
+      constructor.inferFormalTypes(typeSchemaEnvironment);
       engine.beingInferred.remove(target);
     }
   }
diff --git a/pkg/front_end/messages.status b/pkg/front_end/messages.status
index 5ff0e55..6563de2 100644
--- a/pkg/front_end/messages.status
+++ b/pkg/front_end/messages.status
@@ -709,6 +709,8 @@
 OperatorParameterMismatch2/example: Fail
 OperatorWithOptionalFormals/analyzerCode: Fail
 OperatorWithOptionalFormals/example: Fail
+OptionalSuperParameterWithoutInitializer/analyzerCode: Fail
+OptionalSuperParameterWithoutInitializer/example: Fail
 OverrideFewerNamedArguments/example: Fail
 OverrideFewerPositionalArguments/example: Fail
 OverrideMismatchNamedParameter/example: Fail
diff --git a/pkg/front_end/messages.yaml b/pkg/front_end/messages.yaml
index 8f83875..d165d4c 100644
--- a/pkg/front_end/messages.yaml
+++ b/pkg/front_end/messages.yaml
@@ -5516,3 +5516,6 @@
 NonAugmentationClassMemberConflictCause:
   problemMessage: "This is the existing member."
   severity: CONTEXT
+
+OptionalSuperParameterWithoutInitializer:
+  problemMessage: "Type '#type' of the optional super-initializer parameter '#name' doesn't allow 'null', but the parameter doesn't have a default value, and the default value can't be copied from the corresponding parameter of the super constructor."
diff --git a/pkg/front_end/test/spell_checking_list_tests.txt b/pkg/front_end/test/spell_checking_list_tests.txt
index 0a0575a..5f1144f 100644
--- a/pkg/front_end/test/spell_checking_list_tests.txt
+++ b/pkg/front_end/test/spell_checking_list_tests.txt
@@ -81,6 +81,7 @@
 boundarykey
 bowtie
 boz
+bp
 bq
 brand
 brave
@@ -535,6 +536,7 @@
 repro
 reproduce
 reproduction
+req
 resuming
 retaining
 retainingpath
diff --git a/pkg/front_end/testcases/super_parameters/default_values.dart b/pkg/front_end/testcases/super_parameters/default_values.dart
index 515a046..f62c550 100644
--- a/pkg/front_end/testcases/super_parameters/default_values.dart
+++ b/pkg/front_end/testcases/super_parameters/default_values.dart
@@ -106,4 +106,22 @@
   S9([int x = 0]) : s = x - 1;
 }
 
+class Ap {
+  Ap([num x = 3.14]);
+}
+
+class Bp extends Ap {
+  Bp([int super.x]); // Error.
+  Bp.req(int super.x); // Ok.
+}
+
+class An {
+  An({num x = 3.14});
+}
+
+class Bn extends An {
+  Bn({int super.x}); // Error.
+  Bn.req({required int super.x}); // Ok.
+}
+
 main() {}
diff --git a/pkg/front_end/testcases/super_parameters/default_values.dart.strong.expect b/pkg/front_end/testcases/super_parameters/default_values.dart.strong.expect
index 29ffdbc..53f4848 100644
--- a/pkg/front_end/testcases/super_parameters/default_values.dart.strong.expect
+++ b/pkg/front_end/testcases/super_parameters/default_values.dart.strong.expect
@@ -2,11 +2,18 @@
 //
 // Problems in library:
 //
-// pkg/front_end/testcases/super_parameters/default_values.dart:51:17: Error: The parameter 'x' can't have a value of 'null' because of its type 'int', but the implicit default value is 'null'.
-// Try adding either an explicit non-'null' default value or the 'required' modifier.
+// pkg/front_end/testcases/super_parameters/default_values.dart:51:17: Error: Type 'int' of the optional super-initializer parameter 'x' doesn't allow 'null', but the parameter doesn't have a default value, and the default value can't be copied from the corresponding parameter of the super constructor.
 //   C5([int super.x]); // Error.
 //                 ^
 //
+// pkg/front_end/testcases/super_parameters/default_values.dart:114:17: Error: Type 'int' of the optional super-initializer parameter 'x' doesn't allow 'null', but the parameter doesn't have a default value, and the default value can't be copied from the corresponding parameter of the super constructor.
+//   Bp([int super.x]); // Error.
+//                 ^
+//
+// pkg/front_end/testcases/super_parameters/default_values.dart:123:17: Error: Type 'int' of the optional super-initializer parameter 'x' doesn't allow 'null', but the parameter doesn't have a default value, and the default value can't be copied from the corresponding parameter of the super constructor.
+//   Bn({int super.x}); // Error.
+//                 ^
+//
 import self as self;
 import "dart:core" as core;
 
@@ -135,6 +142,32 @@
     : self::S9::s = x.{core::num::-}(1){(core::num) → core::int}, super core::Object::•()
     ;
 }
+class Ap extends core::Object {
+  constructor •([core::num x = #C3]) → self::Ap
+    : super core::Object::•()
+    ;
+}
+class Bp extends self::Ap {
+  constructor •([core::int x = #C4]) → self::Bp
+    : super self::Ap::•(x)
+    ;
+  constructor req(core::int x) → self::Bp
+    : super self::Ap::•(x)
+    ;
+}
+class An extends core::Object {
+  constructor •({core::num x = #C3}) → self::An
+    : super core::Object::•()
+    ;
+}
+class Bn extends self::An {
+  constructor •({core::int x = #C4}) → self::Bn
+    : super self::An::•(x: x)
+    ;
+  constructor req({required core::int x = #C4}) → self::Bn
+    : super self::An::•(x: x)
+    ;
+}
 static method main() → dynamic {}
 
 constants  {
diff --git a/pkg/front_end/testcases/super_parameters/default_values.dart.strong.transformed.expect b/pkg/front_end/testcases/super_parameters/default_values.dart.strong.transformed.expect
index 29ffdbc..53f4848 100644
--- a/pkg/front_end/testcases/super_parameters/default_values.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/super_parameters/default_values.dart.strong.transformed.expect
@@ -2,11 +2,18 @@
 //
 // Problems in library:
 //
-// pkg/front_end/testcases/super_parameters/default_values.dart:51:17: Error: The parameter 'x' can't have a value of 'null' because of its type 'int', but the implicit default value is 'null'.
-// Try adding either an explicit non-'null' default value or the 'required' modifier.
+// pkg/front_end/testcases/super_parameters/default_values.dart:51:17: Error: Type 'int' of the optional super-initializer parameter 'x' doesn't allow 'null', but the parameter doesn't have a default value, and the default value can't be copied from the corresponding parameter of the super constructor.
 //   C5([int super.x]); // Error.
 //                 ^
 //
+// pkg/front_end/testcases/super_parameters/default_values.dart:114:17: Error: Type 'int' of the optional super-initializer parameter 'x' doesn't allow 'null', but the parameter doesn't have a default value, and the default value can't be copied from the corresponding parameter of the super constructor.
+//   Bp([int super.x]); // Error.
+//                 ^
+//
+// pkg/front_end/testcases/super_parameters/default_values.dart:123:17: Error: Type 'int' of the optional super-initializer parameter 'x' doesn't allow 'null', but the parameter doesn't have a default value, and the default value can't be copied from the corresponding parameter of the super constructor.
+//   Bn({int super.x}); // Error.
+//                 ^
+//
 import self as self;
 import "dart:core" as core;
 
@@ -135,6 +142,32 @@
     : self::S9::s = x.{core::num::-}(1){(core::num) → core::int}, super core::Object::•()
     ;
 }
+class Ap extends core::Object {
+  constructor •([core::num x = #C3]) → self::Ap
+    : super core::Object::•()
+    ;
+}
+class Bp extends self::Ap {
+  constructor •([core::int x = #C4]) → self::Bp
+    : super self::Ap::•(x)
+    ;
+  constructor req(core::int x) → self::Bp
+    : super self::Ap::•(x)
+    ;
+}
+class An extends core::Object {
+  constructor •({core::num x = #C3}) → self::An
+    : super core::Object::•()
+    ;
+}
+class Bn extends self::An {
+  constructor •({core::int x = #C4}) → self::Bn
+    : super self::An::•(x: x)
+    ;
+  constructor req({required core::int x = #C4}) → self::Bn
+    : super self::An::•(x: x)
+    ;
+}
 static method main() → dynamic {}
 
 constants  {
diff --git a/pkg/front_end/testcases/super_parameters/default_values.dart.textual_outline.expect b/pkg/front_end/testcases/super_parameters/default_values.dart.textual_outline.expect
index 1cb3689..9f3486c 100644
--- a/pkg/front_end/testcases/super_parameters/default_values.dart.textual_outline.expect
+++ b/pkg/front_end/testcases/super_parameters/default_values.dart.textual_outline.expect
@@ -81,4 +81,18 @@
   int s;
   S9([int x = 0]) : s = x - 1;
 }
+class Ap {
+  Ap([num x = 3.14]);
+}
+class Bp extends Ap {
+  Bp([int super.x]);
+  Bp.req(int super.x);
+}
+class An {
+  An({num x = 3.14});
+}
+class Bn extends An {
+  Bn({int super.x});
+  Bn.req({required int super.x});
+}
 main() {}
diff --git a/pkg/front_end/testcases/super_parameters/default_values.dart.weak.expect b/pkg/front_end/testcases/super_parameters/default_values.dart.weak.expect
index 29ffdbc..53f4848 100644
--- a/pkg/front_end/testcases/super_parameters/default_values.dart.weak.expect
+++ b/pkg/front_end/testcases/super_parameters/default_values.dart.weak.expect
@@ -2,11 +2,18 @@
 //
 // Problems in library:
 //
-// pkg/front_end/testcases/super_parameters/default_values.dart:51:17: Error: The parameter 'x' can't have a value of 'null' because of its type 'int', but the implicit default value is 'null'.
-// Try adding either an explicit non-'null' default value or the 'required' modifier.
+// pkg/front_end/testcases/super_parameters/default_values.dart:51:17: Error: Type 'int' of the optional super-initializer parameter 'x' doesn't allow 'null', but the parameter doesn't have a default value, and the default value can't be copied from the corresponding parameter of the super constructor.
 //   C5([int super.x]); // Error.
 //                 ^
 //
+// pkg/front_end/testcases/super_parameters/default_values.dart:114:17: Error: Type 'int' of the optional super-initializer parameter 'x' doesn't allow 'null', but the parameter doesn't have a default value, and the default value can't be copied from the corresponding parameter of the super constructor.
+//   Bp([int super.x]); // Error.
+//                 ^
+//
+// pkg/front_end/testcases/super_parameters/default_values.dart:123:17: Error: Type 'int' of the optional super-initializer parameter 'x' doesn't allow 'null', but the parameter doesn't have a default value, and the default value can't be copied from the corresponding parameter of the super constructor.
+//   Bn({int super.x}); // Error.
+//                 ^
+//
 import self as self;
 import "dart:core" as core;
 
@@ -135,6 +142,32 @@
     : self::S9::s = x.{core::num::-}(1){(core::num) → core::int}, super core::Object::•()
     ;
 }
+class Ap extends core::Object {
+  constructor •([core::num x = #C3]) → self::Ap
+    : super core::Object::•()
+    ;
+}
+class Bp extends self::Ap {
+  constructor •([core::int x = #C4]) → self::Bp
+    : super self::Ap::•(x)
+    ;
+  constructor req(core::int x) → self::Bp
+    : super self::Ap::•(x)
+    ;
+}
+class An extends core::Object {
+  constructor •({core::num x = #C3}) → self::An
+    : super core::Object::•()
+    ;
+}
+class Bn extends self::An {
+  constructor •({core::int x = #C4}) → self::Bn
+    : super self::An::•(x: x)
+    ;
+  constructor req({required core::int x = #C4}) → self::Bn
+    : super self::An::•(x: x)
+    ;
+}
 static method main() → dynamic {}
 
 constants  {
diff --git a/pkg/front_end/testcases/super_parameters/default_values.dart.weak.modular.expect b/pkg/front_end/testcases/super_parameters/default_values.dart.weak.modular.expect
index 29ffdbc..53f4848 100644
--- a/pkg/front_end/testcases/super_parameters/default_values.dart.weak.modular.expect
+++ b/pkg/front_end/testcases/super_parameters/default_values.dart.weak.modular.expect
@@ -2,11 +2,18 @@
 //
 // Problems in library:
 //
-// pkg/front_end/testcases/super_parameters/default_values.dart:51:17: Error: The parameter 'x' can't have a value of 'null' because of its type 'int', but the implicit default value is 'null'.
-// Try adding either an explicit non-'null' default value or the 'required' modifier.
+// pkg/front_end/testcases/super_parameters/default_values.dart:51:17: Error: Type 'int' of the optional super-initializer parameter 'x' doesn't allow 'null', but the parameter doesn't have a default value, and the default value can't be copied from the corresponding parameter of the super constructor.
 //   C5([int super.x]); // Error.
 //                 ^
 //
+// pkg/front_end/testcases/super_parameters/default_values.dart:114:17: Error: Type 'int' of the optional super-initializer parameter 'x' doesn't allow 'null', but the parameter doesn't have a default value, and the default value can't be copied from the corresponding parameter of the super constructor.
+//   Bp([int super.x]); // Error.
+//                 ^
+//
+// pkg/front_end/testcases/super_parameters/default_values.dart:123:17: Error: Type 'int' of the optional super-initializer parameter 'x' doesn't allow 'null', but the parameter doesn't have a default value, and the default value can't be copied from the corresponding parameter of the super constructor.
+//   Bn({int super.x}); // Error.
+//                 ^
+//
 import self as self;
 import "dart:core" as core;
 
@@ -135,6 +142,32 @@
     : self::S9::s = x.{core::num::-}(1){(core::num) → core::int}, super core::Object::•()
     ;
 }
+class Ap extends core::Object {
+  constructor •([core::num x = #C3]) → self::Ap
+    : super core::Object::•()
+    ;
+}
+class Bp extends self::Ap {
+  constructor •([core::int x = #C4]) → self::Bp
+    : super self::Ap::•(x)
+    ;
+  constructor req(core::int x) → self::Bp
+    : super self::Ap::•(x)
+    ;
+}
+class An extends core::Object {
+  constructor •({core::num x = #C3}) → self::An
+    : super core::Object::•()
+    ;
+}
+class Bn extends self::An {
+  constructor •({core::int x = #C4}) → self::Bn
+    : super self::An::•(x: x)
+    ;
+  constructor req({required core::int x = #C4}) → self::Bn
+    : super self::An::•(x: x)
+    ;
+}
 static method main() → dynamic {}
 
 constants  {
diff --git a/pkg/front_end/testcases/super_parameters/default_values.dart.weak.outline.expect b/pkg/front_end/testcases/super_parameters/default_values.dart.weak.outline.expect
index aca3fd0..e843595 100644
--- a/pkg/front_end/testcases/super_parameters/default_values.dart.weak.outline.expect
+++ b/pkg/front_end/testcases/super_parameters/default_values.dart.weak.outline.expect
@@ -2,11 +2,18 @@
 //
 // Problems in library:
 //
-// pkg/front_end/testcases/super_parameters/default_values.dart:51:17: Error: The parameter 'x' can't have a value of 'null' because of its type 'int', but the implicit default value is 'null'.
-// Try adding either an explicit non-'null' default value or the 'required' modifier.
+// pkg/front_end/testcases/super_parameters/default_values.dart:51:17: Error: Type 'int' of the optional super-initializer parameter 'x' doesn't allow 'null', but the parameter doesn't have a default value, and the default value can't be copied from the corresponding parameter of the super constructor.
 //   C5([int super.x]); // Error.
 //                 ^
 //
+// pkg/front_end/testcases/super_parameters/default_values.dart:114:17: Error: Type 'int' of the optional super-initializer parameter 'x' doesn't allow 'null', but the parameter doesn't have a default value, and the default value can't be copied from the corresponding parameter of the super constructor.
+//   Bp([int super.x]); // Error.
+//                 ^
+//
+// pkg/front_end/testcases/super_parameters/default_values.dart:123:17: Error: Type 'int' of the optional super-initializer parameter 'x' doesn't allow 'null', but the parameter doesn't have a default value, and the default value can't be copied from the corresponding parameter of the super constructor.
+//   Bn({int super.x}); // Error.
+//                 ^
+//
 import self as self;
 import "dart:core" as core;
 
@@ -114,5 +121,25 @@
   constructor •([core::int x = 0]) → self::S9
     ;
 }
+class Ap extends core::Object {
+  constructor •([core::num x = 3.14]) → self::Ap
+    ;
+}
+class Bp extends self::Ap {
+  constructor •([core::int x]) → self::Bp
+    ;
+  constructor req(core::int x) → self::Bp
+    ;
+}
+class An extends core::Object {
+  constructor •({core::num x = 3.14}) → self::An
+    ;
+}
+class Bn extends self::An {
+  constructor •({core::int x}) → self::Bn
+    ;
+  constructor req({required core::int x}) → self::Bn
+    ;
+}
 static method main() → dynamic
   ;
diff --git a/pkg/front_end/testcases/super_parameters/default_values.dart.weak.transformed.expect b/pkg/front_end/testcases/super_parameters/default_values.dart.weak.transformed.expect
index 29ffdbc..53f4848 100644
--- a/pkg/front_end/testcases/super_parameters/default_values.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/super_parameters/default_values.dart.weak.transformed.expect
@@ -2,11 +2,18 @@
 //
 // Problems in library:
 //
-// pkg/front_end/testcases/super_parameters/default_values.dart:51:17: Error: The parameter 'x' can't have a value of 'null' because of its type 'int', but the implicit default value is 'null'.
-// Try adding either an explicit non-'null' default value or the 'required' modifier.
+// pkg/front_end/testcases/super_parameters/default_values.dart:51:17: Error: Type 'int' of the optional super-initializer parameter 'x' doesn't allow 'null', but the parameter doesn't have a default value, and the default value can't be copied from the corresponding parameter of the super constructor.
 //   C5([int super.x]); // Error.
 //                 ^
 //
+// pkg/front_end/testcases/super_parameters/default_values.dart:114:17: Error: Type 'int' of the optional super-initializer parameter 'x' doesn't allow 'null', but the parameter doesn't have a default value, and the default value can't be copied from the corresponding parameter of the super constructor.
+//   Bp([int super.x]); // Error.
+//                 ^
+//
+// pkg/front_end/testcases/super_parameters/default_values.dart:123:17: Error: Type 'int' of the optional super-initializer parameter 'x' doesn't allow 'null', but the parameter doesn't have a default value, and the default value can't be copied from the corresponding parameter of the super constructor.
+//   Bn({int super.x}); // Error.
+//                 ^
+//
 import self as self;
 import "dart:core" as core;
 
@@ -135,6 +142,32 @@
     : self::S9::s = x.{core::num::-}(1){(core::num) → core::int}, super core::Object::•()
     ;
 }
+class Ap extends core::Object {
+  constructor •([core::num x = #C3]) → self::Ap
+    : super core::Object::•()
+    ;
+}
+class Bp extends self::Ap {
+  constructor •([core::int x = #C4]) → self::Bp
+    : super self::Ap::•(x)
+    ;
+  constructor req(core::int x) → self::Bp
+    : super self::Ap::•(x)
+    ;
+}
+class An extends core::Object {
+  constructor •({core::num x = #C3}) → self::An
+    : super core::Object::•()
+    ;
+}
+class Bn extends self::An {
+  constructor •({core::int x = #C4}) → self::Bn
+    : super self::An::•(x: x)
+    ;
+  constructor req({required core::int x = #C4}) → self::Bn
+    : super self::An::•(x: x)
+    ;
+}
 static method main() → dynamic {}
 
 constants  {
diff --git a/pkg/front_end/testcases/super_parameters/issue47741.dart.strong.expect b/pkg/front_end/testcases/super_parameters/issue47741.dart.strong.expect
index d463400..0bcb96a 100644
--- a/pkg/front_end/testcases/super_parameters/issue47741.dart.strong.expect
+++ b/pkg/front_end/testcases/super_parameters/issue47741.dart.strong.expect
@@ -1,4 +1,15 @@
 library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/super_parameters/issue47741.dart:10:23: Error: The argument type 'double Function<T1>(int)' can't be assigned to the parameter type 'int Function<T>(int)'.
+//   B.sub1(double super.bar1<T1>(int a1),);
+//                       ^
+//
+// pkg/front_end/testcases/super_parameters/issue47741.dart:11:23: Error: The argument type 'double Function<T2>(int)' can't be assigned to the parameter type 'int Function<T>(int)'.
+//   B.sub2(double super.bar2<T2>(int a2),);
+//                       ^
+//
 import self as self;
 import "dart:core" as core;
 
@@ -9,10 +20,14 @@
 }
 class B extends self::A {
   constructor sub1(<T1 extends core::Object? = dynamic>(core::int) → core::double bar1) → self::B
-    : super self::A::•(bar1)
+    : super self::A::•(invalid-expression "pkg/front_end/testcases/super_parameters/issue47741.dart:10:23: Error: The argument type 'double Function<T1>(int)' can't be assigned to the parameter type 'int Function<T>(int)'.
+  B.sub1(double super.bar1<T1>(int a1),);
+                      ^" in bar1 as{TypeError,ForNonNullableByDefault} <T extends core::Object? = dynamic>(core::int) → core::int)
     ;
   constructor sub2(<T2 extends core::Object? = dynamic>(core::int) → core::double bar2) → self::B
-    : super self::A::•(bar2)
+    : super self::A::•(invalid-expression "pkg/front_end/testcases/super_parameters/issue47741.dart:11:23: Error: The argument type 'double Function<T2>(int)' can't be assigned to the parameter type 'int Function<T>(int)'.
+  B.sub2(double super.bar2<T2>(int a2),);
+                      ^" in bar2 as{TypeError,ForNonNullableByDefault} <T extends core::Object? = dynamic>(core::int) → core::int)
     ;
 }
 static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/super_parameters/issue47741.dart.strong.transformed.expect b/pkg/front_end/testcases/super_parameters/issue47741.dart.strong.transformed.expect
index d463400..0bcb96a 100644
--- a/pkg/front_end/testcases/super_parameters/issue47741.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/super_parameters/issue47741.dart.strong.transformed.expect
@@ -1,4 +1,15 @@
 library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/super_parameters/issue47741.dart:10:23: Error: The argument type 'double Function<T1>(int)' can't be assigned to the parameter type 'int Function<T>(int)'.
+//   B.sub1(double super.bar1<T1>(int a1),);
+//                       ^
+//
+// pkg/front_end/testcases/super_parameters/issue47741.dart:11:23: Error: The argument type 'double Function<T2>(int)' can't be assigned to the parameter type 'int Function<T>(int)'.
+//   B.sub2(double super.bar2<T2>(int a2),);
+//                       ^
+//
 import self as self;
 import "dart:core" as core;
 
@@ -9,10 +20,14 @@
 }
 class B extends self::A {
   constructor sub1(<T1 extends core::Object? = dynamic>(core::int) → core::double bar1) → self::B
-    : super self::A::•(bar1)
+    : super self::A::•(invalid-expression "pkg/front_end/testcases/super_parameters/issue47741.dart:10:23: Error: The argument type 'double Function<T1>(int)' can't be assigned to the parameter type 'int Function<T>(int)'.
+  B.sub1(double super.bar1<T1>(int a1),);
+                      ^" in bar1 as{TypeError,ForNonNullableByDefault} <T extends core::Object? = dynamic>(core::int) → core::int)
     ;
   constructor sub2(<T2 extends core::Object? = dynamic>(core::int) → core::double bar2) → self::B
-    : super self::A::•(bar2)
+    : super self::A::•(invalid-expression "pkg/front_end/testcases/super_parameters/issue47741.dart:11:23: Error: The argument type 'double Function<T2>(int)' can't be assigned to the parameter type 'int Function<T>(int)'.
+  B.sub2(double super.bar2<T2>(int a2),);
+                      ^" in bar2 as{TypeError,ForNonNullableByDefault} <T extends core::Object? = dynamic>(core::int) → core::int)
     ;
 }
 static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/super_parameters/issue47741.dart.weak.expect b/pkg/front_end/testcases/super_parameters/issue47741.dart.weak.expect
index d463400..0bcb96a 100644
--- a/pkg/front_end/testcases/super_parameters/issue47741.dart.weak.expect
+++ b/pkg/front_end/testcases/super_parameters/issue47741.dart.weak.expect
@@ -1,4 +1,15 @@
 library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/super_parameters/issue47741.dart:10:23: Error: The argument type 'double Function<T1>(int)' can't be assigned to the parameter type 'int Function<T>(int)'.
+//   B.sub1(double super.bar1<T1>(int a1),);
+//                       ^
+//
+// pkg/front_end/testcases/super_parameters/issue47741.dart:11:23: Error: The argument type 'double Function<T2>(int)' can't be assigned to the parameter type 'int Function<T>(int)'.
+//   B.sub2(double super.bar2<T2>(int a2),);
+//                       ^
+//
 import self as self;
 import "dart:core" as core;
 
@@ -9,10 +20,14 @@
 }
 class B extends self::A {
   constructor sub1(<T1 extends core::Object? = dynamic>(core::int) → core::double bar1) → self::B
-    : super self::A::•(bar1)
+    : super self::A::•(invalid-expression "pkg/front_end/testcases/super_parameters/issue47741.dart:10:23: Error: The argument type 'double Function<T1>(int)' can't be assigned to the parameter type 'int Function<T>(int)'.
+  B.sub1(double super.bar1<T1>(int a1),);
+                      ^" in bar1 as{TypeError,ForNonNullableByDefault} <T extends core::Object? = dynamic>(core::int) → core::int)
     ;
   constructor sub2(<T2 extends core::Object? = dynamic>(core::int) → core::double bar2) → self::B
-    : super self::A::•(bar2)
+    : super self::A::•(invalid-expression "pkg/front_end/testcases/super_parameters/issue47741.dart:11:23: Error: The argument type 'double Function<T2>(int)' can't be assigned to the parameter type 'int Function<T>(int)'.
+  B.sub2(double super.bar2<T2>(int a2),);
+                      ^" in bar2 as{TypeError,ForNonNullableByDefault} <T extends core::Object? = dynamic>(core::int) → core::int)
     ;
 }
 static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/super_parameters/issue47741.dart.weak.modular.expect b/pkg/front_end/testcases/super_parameters/issue47741.dart.weak.modular.expect
index d463400..0bcb96a 100644
--- a/pkg/front_end/testcases/super_parameters/issue47741.dart.weak.modular.expect
+++ b/pkg/front_end/testcases/super_parameters/issue47741.dart.weak.modular.expect
@@ -1,4 +1,15 @@
 library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/super_parameters/issue47741.dart:10:23: Error: The argument type 'double Function<T1>(int)' can't be assigned to the parameter type 'int Function<T>(int)'.
+//   B.sub1(double super.bar1<T1>(int a1),);
+//                       ^
+//
+// pkg/front_end/testcases/super_parameters/issue47741.dart:11:23: Error: The argument type 'double Function<T2>(int)' can't be assigned to the parameter type 'int Function<T>(int)'.
+//   B.sub2(double super.bar2<T2>(int a2),);
+//                       ^
+//
 import self as self;
 import "dart:core" as core;
 
@@ -9,10 +20,14 @@
 }
 class B extends self::A {
   constructor sub1(<T1 extends core::Object? = dynamic>(core::int) → core::double bar1) → self::B
-    : super self::A::•(bar1)
+    : super self::A::•(invalid-expression "pkg/front_end/testcases/super_parameters/issue47741.dart:10:23: Error: The argument type 'double Function<T1>(int)' can't be assigned to the parameter type 'int Function<T>(int)'.
+  B.sub1(double super.bar1<T1>(int a1),);
+                      ^" in bar1 as{TypeError,ForNonNullableByDefault} <T extends core::Object? = dynamic>(core::int) → core::int)
     ;
   constructor sub2(<T2 extends core::Object? = dynamic>(core::int) → core::double bar2) → self::B
-    : super self::A::•(bar2)
+    : super self::A::•(invalid-expression "pkg/front_end/testcases/super_parameters/issue47741.dart:11:23: Error: The argument type 'double Function<T2>(int)' can't be assigned to the parameter type 'int Function<T>(int)'.
+  B.sub2(double super.bar2<T2>(int a2),);
+                      ^" in bar2 as{TypeError,ForNonNullableByDefault} <T extends core::Object? = dynamic>(core::int) → core::int)
     ;
 }
 static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/super_parameters/issue47741.dart.weak.transformed.expect b/pkg/front_end/testcases/super_parameters/issue47741.dart.weak.transformed.expect
index d463400..0bcb96a 100644
--- a/pkg/front_end/testcases/super_parameters/issue47741.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/super_parameters/issue47741.dart.weak.transformed.expect
@@ -1,4 +1,15 @@
 library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/super_parameters/issue47741.dart:10:23: Error: The argument type 'double Function<T1>(int)' can't be assigned to the parameter type 'int Function<T>(int)'.
+//   B.sub1(double super.bar1<T1>(int a1),);
+//                       ^
+//
+// pkg/front_end/testcases/super_parameters/issue47741.dart:11:23: Error: The argument type 'double Function<T2>(int)' can't be assigned to the parameter type 'int Function<T>(int)'.
+//   B.sub2(double super.bar2<T2>(int a2),);
+//                       ^
+//
 import self as self;
 import "dart:core" as core;
 
@@ -9,10 +20,14 @@
 }
 class B extends self::A {
   constructor sub1(<T1 extends core::Object? = dynamic>(core::int) → core::double bar1) → self::B
-    : super self::A::•(bar1)
+    : super self::A::•(invalid-expression "pkg/front_end/testcases/super_parameters/issue47741.dart:10:23: Error: The argument type 'double Function<T1>(int)' can't be assigned to the parameter type 'int Function<T>(int)'.
+  B.sub1(double super.bar1<T1>(int a1),);
+                      ^" in bar1 as{TypeError,ForNonNullableByDefault} <T extends core::Object? = dynamic>(core::int) → core::int)
     ;
   constructor sub2(<T2 extends core::Object? = dynamic>(core::int) → core::double bar2) → self::B
-    : super self::A::•(bar2)
+    : super self::A::•(invalid-expression "pkg/front_end/testcases/super_parameters/issue47741.dart:11:23: Error: The argument type 'double Function<T2>(int)' can't be assigned to the parameter type 'int Function<T>(int)'.
+  B.sub2(double super.bar2<T2>(int a2),);
+                      ^" in bar2 as{TypeError,ForNonNullableByDefault} <T extends core::Object? = dynamic>(core::int) → core::int)
     ;
 }
 static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/super_parameters/super_parameters_with_types_and_default_values.dart.strong.expect b/pkg/front_end/testcases/super_parameters/super_parameters_with_types_and_default_values.dart.strong.expect
index 3bd8f09..43d6051 100644
--- a/pkg/front_end/testcases/super_parameters/super_parameters_with_types_and_default_values.dart.strong.expect
+++ b/pkg/front_end/testcases/super_parameters/super_parameters_with_types_and_default_values.dart.strong.expect
@@ -11,7 +11,7 @@
 }
 class C extends self::S {
   field core::int c1;
-  constructor •(core::int c1, [dynamic s1 = #C1, core::int x = #C3, dynamic s2 = #C2]) → self::C
+  constructor •(core::int c1, [core::int s1 = #C1, core::int x = #C3, core::int s2 = #C2]) → self::C
     : self::C::c1 = c1, super self::S::•(s1, s2)
     ;
 }
diff --git a/pkg/front_end/testcases/super_parameters/super_parameters_with_types_and_default_values.dart.strong.transformed.expect b/pkg/front_end/testcases/super_parameters/super_parameters_with_types_and_default_values.dart.strong.transformed.expect
index 3bd8f09..43d6051 100644
--- a/pkg/front_end/testcases/super_parameters/super_parameters_with_types_and_default_values.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/super_parameters/super_parameters_with_types_and_default_values.dart.strong.transformed.expect
@@ -11,7 +11,7 @@
 }
 class C extends self::S {
   field core::int c1;
-  constructor •(core::int c1, [dynamic s1 = #C1, core::int x = #C3, dynamic s2 = #C2]) → self::C
+  constructor •(core::int c1, [core::int s1 = #C1, core::int x = #C3, core::int s2 = #C2]) → self::C
     : self::C::c1 = c1, super self::S::•(s1, s2)
     ;
 }
diff --git a/pkg/front_end/testcases/super_parameters/super_parameters_with_types_and_default_values.dart.weak.expect b/pkg/front_end/testcases/super_parameters/super_parameters_with_types_and_default_values.dart.weak.expect
index 3bd8f09..43d6051 100644
--- a/pkg/front_end/testcases/super_parameters/super_parameters_with_types_and_default_values.dart.weak.expect
+++ b/pkg/front_end/testcases/super_parameters/super_parameters_with_types_and_default_values.dart.weak.expect
@@ -11,7 +11,7 @@
 }
 class C extends self::S {
   field core::int c1;
-  constructor •(core::int c1, [dynamic s1 = #C1, core::int x = #C3, dynamic s2 = #C2]) → self::C
+  constructor •(core::int c1, [core::int s1 = #C1, core::int x = #C3, core::int s2 = #C2]) → self::C
     : self::C::c1 = c1, super self::S::•(s1, s2)
     ;
 }
diff --git a/pkg/front_end/testcases/super_parameters/super_parameters_with_types_and_default_values.dart.weak.modular.expect b/pkg/front_end/testcases/super_parameters/super_parameters_with_types_and_default_values.dart.weak.modular.expect
index 3bd8f09..43d6051 100644
--- a/pkg/front_end/testcases/super_parameters/super_parameters_with_types_and_default_values.dart.weak.modular.expect
+++ b/pkg/front_end/testcases/super_parameters/super_parameters_with_types_and_default_values.dart.weak.modular.expect
@@ -11,7 +11,7 @@
 }
 class C extends self::S {
   field core::int c1;
-  constructor •(core::int c1, [dynamic s1 = #C1, core::int x = #C3, dynamic s2 = #C2]) → self::C
+  constructor •(core::int c1, [core::int s1 = #C1, core::int x = #C3, core::int s2 = #C2]) → self::C
     : self::C::c1 = c1, super self::S::•(s1, s2)
     ;
 }
diff --git a/pkg/front_end/testcases/super_parameters/super_parameters_with_types_and_default_values.dart.weak.outline.expect b/pkg/front_end/testcases/super_parameters/super_parameters_with_types_and_default_values.dart.weak.outline.expect
index aae570e..6cb35c7 100644
--- a/pkg/front_end/testcases/super_parameters/super_parameters_with_types_and_default_values.dart.weak.outline.expect
+++ b/pkg/front_end/testcases/super_parameters/super_parameters_with_types_and_default_values.dart.weak.outline.expect
@@ -10,7 +10,7 @@
 }
 class C extends self::S {
   field core::int c1;
-  constructor •(core::int c1, [dynamic s1 = 1, core::int x = 0, dynamic s2 = 2]) → self::C
+  constructor •(core::int c1, [core::int s1 = 1, core::int x = 0, core::int s2 = 2]) → self::C
     : self::C::c1 = c1
     ;
 }
diff --git a/pkg/front_end/testcases/super_parameters/super_parameters_with_types_and_default_values.dart.weak.transformed.expect b/pkg/front_end/testcases/super_parameters/super_parameters_with_types_and_default_values.dart.weak.transformed.expect
index 3bd8f09..43d6051 100644
--- a/pkg/front_end/testcases/super_parameters/super_parameters_with_types_and_default_values.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/super_parameters/super_parameters_with_types_and_default_values.dart.weak.transformed.expect
@@ -11,7 +11,7 @@
 }
 class C extends self::S {
   field core::int c1;
-  constructor •(core::int c1, [dynamic s1 = #C1, core::int x = #C3, dynamic s2 = #C2]) → self::C
+  constructor •(core::int c1, [core::int s1 = #C1, core::int x = #C3, core::int s2 = #C2]) → self::C
     : self::C::c1 = c1, super self::S::•(s1, s2)
     ;
 }
diff --git a/runtime/vm/experimental_features.cc b/runtime/vm/experimental_features.cc
index 5200b16..9f2744a 100644
--- a/runtime/vm/experimental_features.cc
+++ b/runtime/vm/experimental_features.cc
@@ -28,6 +28,9 @@
     true,
     true,
     true,
+    true,
+    true,
+    true,
   };
   ASSERT(static_cast<size_t>(feature) < ARRAY_SIZE(kFeatureValues));
   return kFeatureValues[static_cast<int>(feature)];
@@ -45,6 +48,9 @@
     "spread-collections",
     "triple-shift",
     "constructor-tearoffs",
+    "enhanced-enums",
+    "named-arguments-anywhere",
+    "super-parameters",
   };
   ASSERT(static_cast<size_t>(feature) < ARRAY_SIZE(kFeatureNames));
   return kFeatureNames[static_cast<int>(feature)];
diff --git a/runtime/vm/experimental_features.h b/runtime/vm/experimental_features.h
index d1a5abb..c11734d 100644
--- a/runtime/vm/experimental_features.h
+++ b/runtime/vm/experimental_features.h
@@ -24,6 +24,9 @@
   spread_collections,
   triple_shift,
   constructor_tearoffs,
+  enhanced_enums,
+  named_arguments_anywhere,
+  super_parameters,
 };
 
 bool GetExperimentalFeatureDefault(ExperimentalFeature feature);
diff --git a/tests/language/compile_time_constant/p_test.dart b/tests/language/compile_time_constant/p_test.dart
index 133519f..23426eb 100644
--- a/tests/language/compile_time_constant/p_test.dart
+++ b/tests/language/compile_time_constant/p_test.dart
@@ -5,13 +5,11 @@
 import "package:expect/expect.dart";
 
 class A {
-  const A(
-    this.x
-    //   ^
-    // [analyzer] COMPILE_TIME_ERROR.FINAL_INITIALIZED_IN_DECLARATION_AND_CONSTRUCTOR
-    // [cfe] 'x' is a final instance variable that was initialized at the declaration.
-    //   ^
-    // [cfe] Cannot invoke a non-'const' constructor where a const expression is expected.
+  const A(this.x
+      //       ^
+      // [analyzer] COMPILE_TIME_ERROR.FINAL_INITIALIZED_IN_DECLARATION_AND_CONSTRUCTOR
+      // [cfe] 'x' is a final instance variable that was initialized at the declaration.
+      // [cfe] Cannot invoke a non-'const' constructor where a const expression is expected.
       );
   final x = null;
 }
@@ -19,7 +17,7 @@
 class B extends A {
   const B();
   //    ^
-  // [analyzer] COMPILE_TIME_ERROR.NO_DEFAULT_SUPER_CONSTRUCTOR
+  // [analyzer] COMPILE_TIME_ERROR.IMPLICIT_SUPER_INITIALIZER_MISSING_ARGUMENTS
   // [cfe] The superclass, 'A', has no unnamed constructor that takes no arguments.
 }
 
diff --git a/tests/language/const/constructor_super_test.dart b/tests/language/const/constructor_super_test.dart
index f710d15..a5be635 100644
--- a/tests/language/const/constructor_super_test.dart
+++ b/tests/language/const/constructor_super_test.dart
@@ -17,8 +17,10 @@
         super(x);
 
   // Const constructor cannot call non-const super constructor.
-  const B.zerofive() : b = 0, super(5);
-  //                          ^^^^^^^^
+  const B.zerofive()
+      : b = 0,
+        super(5);
+  //    ^^^^^^^^
   // [analyzer] COMPILE_TIME_ERROR.CONST_CONSTRUCTOR_WITH_NON_CONST_SUPER
   // [cfe] A constant constructor can't call a non-constant super constructor.
 }
@@ -29,9 +31,9 @@
   const C.named(x);
   //    ^
   // [analyzer] COMPILE_TIME_ERROR.CONST_CONSTRUCTOR_WITH_NON_CONST_SUPER
-  // [cfe] The superclass, 'A', has no unnamed constructor that takes no arguments.
   //    ^^^^^^^
-  // [analyzer] COMPILE_TIME_ERROR.NO_DEFAULT_SUPER_CONSTRUCTOR
+  // [analyzer] COMPILE_TIME_ERROR.IMPLICIT_SUPER_INITIALIZER_MISSING_ARGUMENTS
+  // [cfe] The superclass, 'A', has no unnamed constructor that takes no arguments.
 }
 
 main() {
diff --git a/tests/language/enum/enhanced_enums_basic_test.dart b/tests/language/enum/enhanced_enums_basic_test.dart
index fee42e2..2b29521 100644
--- a/tests/language/enum/enhanced_enums_basic_test.dart
+++ b/tests/language/enum/enhanced_enums_basic_test.dart
@@ -2,8 +2,6 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-// SharedOptions=--enable-experiment=enhanced-enums
-
 // Test new enhanced enum syntax.
 
 import 'package:expect/expect.dart';
diff --git a/tests/language/enum/enhanced_enums_error_test.dart b/tests/language/enum/enhanced_enums_error_test.dart
index e812324..b56e29c 100644
--- a/tests/language/enum/enhanced_enums_error_test.dart
+++ b/tests/language/enum/enhanced_enums_error_test.dart
@@ -2,8 +2,6 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-// SharedOptions=--enable-experiment=enhanced-enums
-
 // Test errors required by new enhanced enum syntax.
 
 // Enums must satisfy the same requirements as their induced class.
diff --git a/tests/language/enum/enhanced_enums_subtype_error_test.dart b/tests/language/enum/enhanced_enums_subtype_error_test.dart
index 11bfb20..ae0be18 100644
--- a/tests/language/enum/enhanced_enums_subtype_error_test.dart
+++ b/tests/language/enum/enhanced_enums_subtype_error_test.dart
@@ -2,8 +2,6 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-// SharedOptions=--enable-experiment=enhanced-enums
-
 // Test errors required by new enhanced enum syntax.
 
 // Classes which implement `Enum`, but are not `enum` declarations,
diff --git a/tests/language/named_arguments_anywhere/all_kinds_test.dart b/tests/language/named_arguments_anywhere/all_kinds_test.dart
index 38ea69e..004796e 100644
--- a/tests/language/named_arguments_anywhere/all_kinds_test.dart
+++ b/tests/language/named_arguments_anywhere/all_kinds_test.dart
@@ -5,8 +5,6 @@
 // Check that placing a named argument anywhere in the argument list works for
 // all kinds of invocations.
 
-// SharedOptions=--enable-experiment=named-arguments-anywhere
-
 import "package:expect/expect.dart";
 
 List<Object?> arguments = [];
@@ -17,8 +15,7 @@
 }
 
 void runAndCheckEvaluationOrder(
-    List<Object?> expectedArguments,
-    void Function() functionToRun) {
+    List<Object?> expectedArguments, void Function() functionToRun) {
   arguments.clear();
   functionToRun();
   Expect.listEquals(expectedArguments, arguments);
@@ -32,15 +29,20 @@
     Expect.equals(3.14, w);
   }
 
-  A.redir1() : this(evaluate(1), evaluate("2"), z: evaluate(false), w: evaluate(3.14));
+  A.redir1()
+      : this(evaluate(1), evaluate("2"), z: evaluate(false), w: evaluate(3.14));
 
-  A.redir2() : this(evaluate(1), z: evaluate(false), evaluate("2"), w: evaluate(3.14));
+  A.redir2()
+      : this(evaluate(1), z: evaluate(false), evaluate("2"), w: evaluate(3.14));
 
-  A.redir3() : this(z: evaluate(false), evaluate(1), evaluate("2"), w: evaluate(3.14));
+  A.redir3()
+      : this(z: evaluate(false), evaluate(1), evaluate("2"), w: evaluate(3.14));
 
-  A.redir4() : this(w: evaluate(3.14), evaluate(1), evaluate("2"), z: evaluate(false));
+  A.redir4()
+      : this(w: evaluate(3.14), evaluate(1), evaluate("2"), z: evaluate(false));
 
-  A.redir5() : this(evaluate(1), w: evaluate(3.14), evaluate("2"), z: evaluate(false));
+  A.redir5()
+      : this(evaluate(1), w: evaluate(3.14), evaluate("2"), z: evaluate(false));
 
   A.redir6() : this(evaluate(1), w: evaluate(3.14), evaluate("2"));
 
@@ -92,311 +94,341 @@
 
   // StaticInvocation.
   runAndCheckEvaluationOrder([1, "2", false, 3.14], () {
-      foo(evaluate(1), evaluate("2"), z: evaluate(false), w: evaluate(3.14));
+    foo(evaluate(1), evaluate("2"), z: evaluate(false), w: evaluate(3.14));
   });
   runAndCheckEvaluationOrder([1, false, "2", 3.14], () {
-      foo(evaluate(1), z: evaluate(false), evaluate("2"), w: evaluate(3.14));
+    foo(evaluate(1), z: evaluate(false), evaluate("2"), w: evaluate(3.14));
   });
   runAndCheckEvaluationOrder([false, 1, "2", 3.14], () {
-      foo(z: evaluate(false), evaluate(1), evaluate("2"), w: evaluate(3.14));
+    foo(z: evaluate(false), evaluate(1), evaluate("2"), w: evaluate(3.14));
   });
   runAndCheckEvaluationOrder([3.14, 1, "2", false], () {
-      foo(w: evaluate(3.14), evaluate(1), evaluate("2"), z: evaluate(false));
+    foo(w: evaluate(3.14), evaluate(1), evaluate("2"), z: evaluate(false));
   });
   runAndCheckEvaluationOrder([1, 3.14, "2", false], () {
-      foo(evaluate(1), w: evaluate(3.14), evaluate("2"), z: evaluate(false));
+    foo(evaluate(1), w: evaluate(3.14), evaluate("2"), z: evaluate(false));
   });
   runAndCheckEvaluationOrder([1, 3.14, "2"], () {
-      foo(evaluate(1), w: evaluate(3.14), evaluate("2"));
+    foo(evaluate(1), w: evaluate(3.14), evaluate("2"));
   });
 
   // FactoryConstructorInvocation.
   runAndCheckEvaluationOrder([1, "2", false, 3.14], () {
-      A.foo(evaluate(1), evaluate("2"), z: evaluate(false), w: evaluate(3.14));
+    A.foo(evaluate(1), evaluate("2"), z: evaluate(false), w: evaluate(3.14));
   });
   runAndCheckEvaluationOrder([1, false, "2", 3.14], () {
-      A.foo(evaluate(1), z: evaluate(false), evaluate("2"), w: evaluate(3.14));
+    A.foo(evaluate(1), z: evaluate(false), evaluate("2"), w: evaluate(3.14));
   });
   runAndCheckEvaluationOrder([false, 1, "2", 3.14], () {
-      A.foo(z: evaluate(false), evaluate(1), evaluate("2"), w: evaluate(3.14));
+    A.foo(z: evaluate(false), evaluate(1), evaluate("2"), w: evaluate(3.14));
   });
   runAndCheckEvaluationOrder([1, "2", false, 3.14], () {
-      B.foo(evaluate(1), evaluate("2"), z: evaluate(false), w: evaluate(3.14));
+    B.foo(evaluate(1), evaluate("2"), z: evaluate(false), w: evaluate(3.14));
   });
   runAndCheckEvaluationOrder([1, false, "2", 3.14], () {
-      B.foo(evaluate(1), z: evaluate(false), evaluate("2"), w: evaluate(3.14));
+    B.foo(evaluate(1), z: evaluate(false), evaluate("2"), w: evaluate(3.14));
   });
   runAndCheckEvaluationOrder([false, 1, "2", 3.14], () {
-      B.foo(z: evaluate(false), evaluate(1), evaluate("2"), w: evaluate(3.14));
+    B.foo(z: evaluate(false), evaluate(1), evaluate("2"), w: evaluate(3.14));
   });
   runAndCheckEvaluationOrder([3.14, 1, "2", false], () {
-      B.foo(w: evaluate(3.14), evaluate(1), evaluate("2"), z: evaluate(false));
+    B.foo(w: evaluate(3.14), evaluate(1), evaluate("2"), z: evaluate(false));
   });
   runAndCheckEvaluationOrder([1, 3.14, "2", false], () {
-      B.foo(evaluate(1), w: evaluate(3.14), evaluate("2"), z: evaluate(false));
+    B.foo(evaluate(1), w: evaluate(3.14), evaluate("2"), z: evaluate(false));
   });
   runAndCheckEvaluationOrder([1, 3.14, "2"], () {
-      B.foo(evaluate(1), w: evaluate(3.14), evaluate("2"));
+    B.foo(evaluate(1), w: evaluate(3.14), evaluate("2"));
   });
 
   // ConstructorInvocation.
   runAndCheckEvaluationOrder([1, "2", false, 3.14], () {
-      A(evaluate(1), evaluate("2"), z: evaluate(false), w: evaluate(3.14));
+    A(evaluate(1), evaluate("2"), z: evaluate(false), w: evaluate(3.14));
   });
   runAndCheckEvaluationOrder([1, false, "2", 3.14], () {
-      A(evaluate(1), z: evaluate(false), evaluate("2"), w: evaluate(3.14));
+    A(evaluate(1), z: evaluate(false), evaluate("2"), w: evaluate(3.14));
   });
   runAndCheckEvaluationOrder([false, 1, "2", 3.14], () {
-      A(z: evaluate(false), evaluate(1), evaluate("2"), w: evaluate(3.14));
+    A(z: evaluate(false), evaluate(1), evaluate("2"), w: evaluate(3.14));
   });
   runAndCheckEvaluationOrder([1, "2", false, 3.14], () {
-      B(evaluate(1), evaluate("2"), z: evaluate(false), w: evaluate(3.14));
+    B(evaluate(1), evaluate("2"), z: evaluate(false), w: evaluate(3.14));
   });
   runAndCheckEvaluationOrder([1, false, "2", 3.14], () {
-      B(evaluate(1), z: evaluate(false), evaluate("2"), w: evaluate(3.14));
+    B(evaluate(1), z: evaluate(false), evaluate("2"), w: evaluate(3.14));
   });
   runAndCheckEvaluationOrder([false, 1, "2", 3.14], () {
-      B(z: evaluate(false), evaluate(1), evaluate("2"), w: evaluate(3.14));
+    B(z: evaluate(false), evaluate(1), evaluate("2"), w: evaluate(3.14));
   });
   runAndCheckEvaluationOrder([3.14, 1, "2", false], () {
-      B(w: evaluate(3.14), evaluate(1), evaluate("2"), z: evaluate(false));
+    B(w: evaluate(3.14), evaluate(1), evaluate("2"), z: evaluate(false));
   });
   runAndCheckEvaluationOrder([1, 3.14, "2", false], () {
-      B(evaluate(1), w: evaluate(3.14), evaluate("2"), z: evaluate(false));
+    B(evaluate(1), w: evaluate(3.14), evaluate("2"), z: evaluate(false));
   });
   runAndCheckEvaluationOrder([1, 3.14, "2"], () {
-      B(evaluate(1), w: evaluate(3.14), evaluate("2"));
+    B(evaluate(1), w: evaluate(3.14), evaluate("2"));
   });
 
   // DynamicInvocation.
   runAndCheckEvaluationOrder([1, "2", false, 3.14], () {
-      d(evaluate(1), evaluate("2"), z: evaluate(false), w: evaluate(3.14));
+    d(evaluate(1), evaluate("2"), z: evaluate(false), w: evaluate(3.14));
   });
   runAndCheckEvaluationOrder([1, false, "2", 3.14], () {
-      d(evaluate(1), z: evaluate(false), evaluate("2"), w: evaluate(3.14));
+    d(evaluate(1), z: evaluate(false), evaluate("2"), w: evaluate(3.14));
   });
   runAndCheckEvaluationOrder([false, 1, "2", 3.14], () {
-      d(z: evaluate(false), evaluate(1), evaluate("2"), w: evaluate(3.14));
+    d(z: evaluate(false), evaluate(1), evaluate("2"), w: evaluate(3.14));
   });
   runAndCheckEvaluationOrder([3.14, 1, "2", false], () {
-      d(w: evaluate(3.14), evaluate(1), evaluate("2"), z: evaluate(false));
+    d(w: evaluate(3.14), evaluate(1), evaluate("2"), z: evaluate(false));
   });
   runAndCheckEvaluationOrder([1, 3.14, "2", false], () {
-      d(evaluate(1), w: evaluate(3.14), evaluate("2"), z: evaluate(false));
+    d(evaluate(1), w: evaluate(3.14), evaluate("2"), z: evaluate(false));
   });
   runAndCheckEvaluationOrder([1, 3.14, "2"], () {
-      d(evaluate(1), w: evaluate(3.14), evaluate("2"));
+    d(evaluate(1), w: evaluate(3.14), evaluate("2"));
   });
 
   // FunctionInvocation.
   runAndCheckEvaluationOrder([1, "2", false, 3.14], () {
-      f(evaluate(1), evaluate("2"), z: evaluate(false), w: evaluate(3.14));
+    f(evaluate(1), evaluate("2"), z: evaluate(false), w: evaluate(3.14));
   });
   runAndCheckEvaluationOrder([1, false, "2", 3.14], () {
-      f(evaluate(1), z: evaluate(false), evaluate("2"), w: evaluate(3.14));
+    f(evaluate(1), z: evaluate(false), evaluate("2"), w: evaluate(3.14));
   });
   runAndCheckEvaluationOrder([false, 1, "2", 3.14], () {
-      f(z: evaluate(false), evaluate(1), evaluate("2"), w: evaluate(3.14));
+    f(z: evaluate(false), evaluate(1), evaluate("2"), w: evaluate(3.14));
   });
   runAndCheckEvaluationOrder([3.14, 1, "2", false], () {
-      f(w: evaluate(3.14), evaluate(1), evaluate("2"), z: evaluate(false));
+    f(w: evaluate(3.14), evaluate(1), evaluate("2"), z: evaluate(false));
   });
   runAndCheckEvaluationOrder([1, 3.14, "2", false], () {
-      f(evaluate(1), w: evaluate(3.14), evaluate("2"), z: evaluate(false));
+    f(evaluate(1), w: evaluate(3.14), evaluate("2"), z: evaluate(false));
   });
   runAndCheckEvaluationOrder([1, 3.14, "2"], () {
-      f(evaluate(1), w: evaluate(3.14), evaluate("2"));
+    f(evaluate(1), w: evaluate(3.14), evaluate("2"));
   });
 
   // InstanceGetterInvocation.
   runAndCheckEvaluationOrder([1, "2", false, 3.14], () {
-      a.property(evaluate(1), evaluate("2"), z: evaluate(false), w: evaluate(3.14));
+    a.property(evaluate(1), evaluate("2"),
+        z: evaluate(false), w: evaluate(3.14));
   });
   runAndCheckEvaluationOrder([1, false, "2", 3.14], () {
-      a.property(evaluate(1), z: evaluate(false), evaluate("2"), w: evaluate(3.14));
+    a.property(evaluate(1),
+        z: evaluate(false), evaluate("2"), w: evaluate(3.14));
   });
   runAndCheckEvaluationOrder([false, 1, "2", 3.14], () {
-      a.property(z: evaluate(false), evaluate(1), evaluate("2"), w: evaluate(3.14));
+    a.property(
+        z: evaluate(false), evaluate(1), evaluate("2"), w: evaluate(3.14));
   });
   runAndCheckEvaluationOrder([3.14, 1, "2", false], () {
-      a.property(w: evaluate(3.14), evaluate(1), evaluate("2"), z: evaluate(false));
+    a.property(
+        w: evaluate(3.14), evaluate(1), evaluate("2"), z: evaluate(false));
   });
   runAndCheckEvaluationOrder([1, 3.14, "2", false], () {
-      a.property(evaluate(1), w: evaluate(3.14), evaluate("2"), z: evaluate(false));
+    a.property(evaluate(1),
+        w: evaluate(3.14), evaluate("2"), z: evaluate(false));
   });
   runAndCheckEvaluationOrder([1, 3.14, "2"], () {
-      a.property(evaluate(1), w: evaluate(3.14), evaluate("2"));
+    a.property(evaluate(1), w: evaluate(3.14), evaluate("2"));
   });
 
   // InstanceInvocation.
   runAndCheckEvaluationOrder([a, 1, "2", false, 3.14], () {
-      evaluate(a).bar(evaluate(1), evaluate("2"), z: evaluate(false), w: evaluate(3.14));
+    evaluate(a)
+        .bar(evaluate(1), evaluate("2"), z: evaluate(false), w: evaluate(3.14));
   });
   runAndCheckEvaluationOrder([a, 1, false, "2", 3.14], () {
-      evaluate(a).bar(evaluate(1), z: evaluate(false), evaluate("2"), w: evaluate(3.14));
+    evaluate(a)
+        .bar(evaluate(1), z: evaluate(false), evaluate("2"), w: evaluate(3.14));
   });
   runAndCheckEvaluationOrder([a, false, 1, "2", 3.14], () {
-      evaluate(a).bar(z: evaluate(false), evaluate(1), evaluate("2"), w: evaluate(3.14));
+    evaluate(a)
+        .bar(z: evaluate(false), evaluate(1), evaluate("2"), w: evaluate(3.14));
   });
   runAndCheckEvaluationOrder([a, 3.14, 1, "2", false], () {
-      evaluate(a).bar(w: evaluate(3.14), evaluate(1), evaluate("2"), z: evaluate(false));
+    evaluate(a)
+        .bar(w: evaluate(3.14), evaluate(1), evaluate("2"), z: evaluate(false));
   });
   runAndCheckEvaluationOrder([a, 1, 3.14, "2", false], () {
-      evaluate(a).bar(evaluate(1), w: evaluate(3.14), evaluate("2"), z: evaluate(false));
+    evaluate(a)
+        .bar(evaluate(1), w: evaluate(3.14), evaluate("2"), z: evaluate(false));
   });
   runAndCheckEvaluationOrder([a, 1, 3.14, "2"], () {
-      evaluate(a).bar(evaluate(1), w: evaluate(3.14), evaluate("2"));
+    evaluate(a).bar(evaluate(1), w: evaluate(3.14), evaluate("2"));
   });
 
   // LocalFunctionInvocation.
   runAndCheckEvaluationOrder([1, "2", false, 3.14], () {
-      local(evaluate(1), evaluate("2"), z: evaluate(false), w: evaluate(3.14));
+    local(evaluate(1), evaluate("2"), z: evaluate(false), w: evaluate(3.14));
   });
   runAndCheckEvaluationOrder([1, false, "2", 3.14], () {
-      local(evaluate(1), z: evaluate(false), evaluate("2"), w: evaluate(3.14));
+    local(evaluate(1), z: evaluate(false), evaluate("2"), w: evaluate(3.14));
   });
   runAndCheckEvaluationOrder([false, 1, "2", 3.14], () {
-      local(z: evaluate(false), evaluate(1), evaluate("2"), w: evaluate(3.14));
+    local(z: evaluate(false), evaluate(1), evaluate("2"), w: evaluate(3.14));
   });
   runAndCheckEvaluationOrder([3.14, 1, "2", false], () {
-      local(w: evaluate(3.14), evaluate(1), evaluate("2"), z: evaluate(false));
+    local(w: evaluate(3.14), evaluate(1), evaluate("2"), z: evaluate(false));
   });
   runAndCheckEvaluationOrder([1, 3.14, "2", false], () {
-      local(evaluate(1), w: evaluate(3.14), evaluate("2"), z: evaluate(false));
+    local(evaluate(1), w: evaluate(3.14), evaluate("2"), z: evaluate(false));
   });
   runAndCheckEvaluationOrder([1, 3.14, "2"], () {
-      local(evaluate(1), w: evaluate(3.14), evaluate("2"));
+    local(evaluate(1), w: evaluate(3.14), evaluate("2"));
   });
 
   // Redirecting generative constructors.
   runAndCheckEvaluationOrder([1, "2", false, 3.14], () {
-      A.redir1();
+    A.redir1();
   });
   runAndCheckEvaluationOrder([1, false, "2", 3.14], () {
-      A.redir2();
+    A.redir2();
   });
   runAndCheckEvaluationOrder([false, 1, "2", 3.14], () {
-      A.redir3();
+    A.redir3();
   });
   runAndCheckEvaluationOrder([3.14, 1, "2", false], () {
-      A.redir4();
+    A.redir4();
   });
   runAndCheckEvaluationOrder([1, 3.14, "2", false], () {
-      A.redir5();
+    A.redir5();
   });
   runAndCheckEvaluationOrder([1, 3.14, "2"], () {
-      A.redir6();
+    A.redir6();
   });
 
   // Redirecting factory constructors.
   runAndCheckEvaluationOrder([1, "2", false, 3.14], () {
-      A.redirFactory(evaluate(1), evaluate("2"), z: evaluate(false), w: evaluate(3.14));
+    A.redirFactory(evaluate(1), evaluate("2"),
+        z: evaluate(false), w: evaluate(3.14));
   });
   runAndCheckEvaluationOrder([1, false, "2", 3.14], () {
-      A.redirFactory(evaluate(1), z: evaluate(false), evaluate("2"), w: evaluate(3.14));
+    A.redirFactory(evaluate(1),
+        z: evaluate(false), evaluate("2"), w: evaluate(3.14));
   });
   runAndCheckEvaluationOrder([false, 1, "2", 3.14], () {
-      A.redirFactory(z: evaluate(false), evaluate(1), evaluate("2"), w: evaluate(3.14));
+    A.redirFactory(
+        z: evaluate(false), evaluate(1), evaluate("2"), w: evaluate(3.14));
   });
   runAndCheckEvaluationOrder([3.14, 1, "2", false], () {
-      A.redirFactory(w: evaluate(3.14), evaluate(1), evaluate("2"), z: evaluate(false));
+    A.redirFactory(
+        w: evaluate(3.14), evaluate(1), evaluate("2"), z: evaluate(false));
   });
   runAndCheckEvaluationOrder([1, 3.14, "2", false], () {
-      A.redirFactory(evaluate(1), w: evaluate(3.14), evaluate("2"), z: evaluate(false));
+    A.redirFactory(evaluate(1),
+        w: evaluate(3.14), evaluate("2"), z: evaluate(false));
   });
   runAndCheckEvaluationOrder([1, 3.14, "2"], () {
-      A.redirFactory(evaluate(1), w: evaluate(3.14), evaluate("2"));
+    A.redirFactory(evaluate(1), w: evaluate(3.14), evaluate("2"));
   });
 
   // Constructor super initializers.
   runAndCheckEvaluationOrder([1, "2", false, 3.14], () {
-      Test.super1();
+    Test.super1();
   });
   runAndCheckEvaluationOrder([1, false, "2", 3.14], () {
-      Test.super2();
+    Test.super2();
   });
   runAndCheckEvaluationOrder([false, 1, "2", 3.14], () {
-      Test.super3();
+    Test.super3();
   });
   runAndCheckEvaluationOrder([3.14, 1, "2", false], () {
-      Test.super4();
+    Test.super4();
   });
   runAndCheckEvaluationOrder([1, 3.14, "2", false], () {
-      Test.super5();
+    Test.super5();
   });
   runAndCheckEvaluationOrder([1, 3.14, "2"], () {
-      Test.super6();
+    Test.super6();
   });
 
   // Implicit .call insertion.
   runAndCheckEvaluationOrder([1, "2", false, 3.14], () {
-      a(evaluate(1), evaluate("2"), z: evaluate(false), w: evaluate(3.14));
+    a(evaluate(1), evaluate("2"), z: evaluate(false), w: evaluate(3.14));
   });
   runAndCheckEvaluationOrder([1, false, "2", 3.14], () {
-      a(evaluate(1), z: evaluate(false), evaluate("2"), w: evaluate(3.14));
+    a(evaluate(1), z: evaluate(false), evaluate("2"), w: evaluate(3.14));
   });
   runAndCheckEvaluationOrder([false, 1, "2", 3.14], () {
-      a(z: evaluate(false), evaluate(1), evaluate("2"), w: evaluate(3.14));
+    a(z: evaluate(false), evaluate(1), evaluate("2"), w: evaluate(3.14));
   });
   runAndCheckEvaluationOrder([3.14, 1, "2", false], () {
-      a(w: evaluate(3.14), evaluate(1), evaluate("2"), z: evaluate(false));
+    a(w: evaluate(3.14), evaluate(1), evaluate("2"), z: evaluate(false));
   });
   runAndCheckEvaluationOrder([1, 3.14, "2", false], () {
-      a(evaluate(1), w: evaluate(3.14), evaluate("2"), z: evaluate(false));
+    a(evaluate(1), w: evaluate(3.14), evaluate("2"), z: evaluate(false));
   });
   runAndCheckEvaluationOrder([1, 3.14, "2"], () {
-      a(evaluate(1), w: evaluate(3.14), evaluate("2"));
+    a(evaluate(1), w: evaluate(3.14), evaluate("2"));
   });
 }
 
 class Test extends A {
   Test() : super(1, "2", z: false, w: 3.14);
 
-  Test.super1() : super(evaluate(1), evaluate("2"), z: evaluate(false), w: evaluate(3.14));
-  Test.super2() : super(evaluate(1), z: evaluate(false), evaluate("2"), w: evaluate(3.14));
-  Test.super3() : super(z: evaluate(false), evaluate(1), evaluate("2"), w: evaluate(3.14));
-  Test.super4() : super(w: evaluate(3.14), evaluate(1), evaluate("2"), z: evaluate(false));
-  Test.super5() : super(evaluate(1), w: evaluate(3.14), evaluate("2"), z: evaluate(false));
+  Test.super1()
+      : super(evaluate(1), evaluate("2"),
+            z: evaluate(false), w: evaluate(3.14));
+  Test.super2()
+      : super(evaluate(1),
+            z: evaluate(false), evaluate("2"), w: evaluate(3.14));
+  Test.super3()
+      : super(
+            z: evaluate(false), evaluate(1), evaluate("2"), w: evaluate(3.14));
+  Test.super4()
+      : super(
+            w: evaluate(3.14), evaluate(1), evaluate("2"), z: evaluate(false));
+  Test.super5()
+      : super(evaluate(1),
+            w: evaluate(3.14), evaluate("2"), z: evaluate(false));
   Test.super6() : super(evaluate(1), w: evaluate(3.14), evaluate("2"));
 
   test() {
     runAndCheckEvaluationOrder([1, "2", false, 3.14], () {
-        super.bar(evaluate(1), evaluate("2"), z: evaluate(false), w: evaluate(3.14));
+      super.bar(evaluate(1), evaluate("2"),
+          z: evaluate(false), w: evaluate(3.14));
     });
     runAndCheckEvaluationOrder([1, false, "2", 3.14], () {
-        super.bar(evaluate(1), z: evaluate(false), evaluate("2"), w: evaluate(3.14));
+      super.bar(evaluate(1),
+          z: evaluate(false), evaluate("2"), w: evaluate(3.14));
     });
     runAndCheckEvaluationOrder([false, 1, "2", 3.14], () {
-        super.bar(z: evaluate(false), evaluate(1), evaluate("2"), w: evaluate(3.14));
+      super.bar(
+          z: evaluate(false), evaluate(1), evaluate("2"), w: evaluate(3.14));
     });
     runAndCheckEvaluationOrder([3.14, 1, "2", false], () {
-        super.bar(w: evaluate(3.14), evaluate(1), evaluate("2"), z: evaluate(false));
+      super.bar(
+          w: evaluate(3.14), evaluate(1), evaluate("2"), z: evaluate(false));
     });
     runAndCheckEvaluationOrder([1, 3.14, "2", false], () {
-        super.bar(evaluate(1), w: evaluate(3.14), evaluate("2"), z: evaluate(false));
+      super.bar(evaluate(1),
+          w: evaluate(3.14), evaluate("2"), z: evaluate(false));
     });
     runAndCheckEvaluationOrder([1, 3.14, "2"], () {
-        super.bar(evaluate(1), w: evaluate(3.14), evaluate("2"));
+      super.bar(evaluate(1), w: evaluate(3.14), evaluate("2"));
     });
 
     // Using super.call() implicitly.
     runAndCheckEvaluationOrder([1, "2", false, 3.14], () {
-        super(evaluate(1), evaluate("2"), z: evaluate(false), w: evaluate(3.14));
+      super(evaluate(1), evaluate("2"), z: evaluate(false), w: evaluate(3.14));
     });
     runAndCheckEvaluationOrder([1, false, "2", 3.14], () {
-        super(evaluate(1), z: evaluate(false), evaluate("2"), w: evaluate(3.14));
+      super(evaluate(1), z: evaluate(false), evaluate("2"), w: evaluate(3.14));
     });
     runAndCheckEvaluationOrder([false, 1, "2", 3.14], () {
-        super(z: evaluate(false), evaluate(1), evaluate("2"), w: evaluate(3.14));
+      super(z: evaluate(false), evaluate(1), evaluate("2"), w: evaluate(3.14));
     });
     runAndCheckEvaluationOrder([3.14, 1, "2", false], () {
-        super(w: evaluate(3.14), evaluate(1), evaluate("2"), z: evaluate(false));
+      super(w: evaluate(3.14), evaluate(1), evaluate("2"), z: evaluate(false));
     });
     runAndCheckEvaluationOrder([1, 3.14, "2", false], () {
-        super(evaluate(1), w: evaluate(3.14), evaluate("2"), z: evaluate(false));
+      super(evaluate(1), w: evaluate(3.14), evaluate("2"), z: evaluate(false));
     });
     runAndCheckEvaluationOrder([1, 3.14, "2"], () {
-        super(evaluate(1), w: evaluate(3.14), evaluate("2"));
+      super(evaluate(1), w: evaluate(3.14), evaluate("2"));
     });
   }
 }
@@ -404,9 +436,10 @@
 extension E on A {
   test() {
     runAndCheckEvaluationOrder(["1", 2], () {
-        method(foo: evaluate("1"), evaluate(2)); // This call.
+      method(foo: evaluate("1"), evaluate(2)); // This call.
     });
   }
+
   method(int bar, {String? foo}) {
     Expect.equals(2, bar);
     Expect.equals("1", foo);
diff --git a/tests/language/named_arguments_anywhere/order_side_effects_error_test.dart b/tests/language/named_arguments_anywhere/order_side_effects_error_test.dart
index 52adfbc..e8a4745 100644
--- a/tests/language/named_arguments_anywhere/order_side_effects_error_test.dart
+++ b/tests/language/named_arguments_anywhere/order_side_effects_error_test.dart
@@ -5,8 +5,6 @@
 // Checks that compile-time errors in the arguments are reported when the named
 // arguments are placed before the positional.
 
-// SharedOptions=--enable-experiment=named-arguments-anywhere
-
 const a42 = const A(42);
 
 class A {
diff --git a/tests/language/named_arguments_anywhere/order_side_effects_ok_test.dart b/tests/language/named_arguments_anywhere/order_side_effects_ok_test.dart
index 9dd9e93..cc87abc 100644
--- a/tests/language/named_arguments_anywhere/order_side_effects_ok_test.dart
+++ b/tests/language/named_arguments_anywhere/order_side_effects_ok_test.dart
@@ -5,8 +5,6 @@
 // Checks that typeinference on arguments continues working after their order is
 // changed.
 
-// SharedOptions=--enable-experiment=named-arguments-anywhere
-
 import "package:expect/expect.dart";
 
 Type? argument = null;
@@ -15,7 +13,8 @@
   argument = X;
 }
 
-void runAndCheckForTypeArgument(Type expectedArgument, void Function() functionToRun) {
+void runAndCheckForTypeArgument(
+    Type expectedArgument, void Function() functionToRun) {
   argument = null;
   functionToRun();
   Expect.equals(expectedArgument, argument);
@@ -44,29 +43,29 @@
 
 void main() {
   runAndCheckForTypeArgument(dynamic, () {
-      fooGeneric(const BGeneric(), y: const BGeneric());
+    fooGeneric(const BGeneric(), y: const BGeneric());
   });
   runAndCheckForTypeArgument(dynamic, () {
-      fooGeneric(y: const BGeneric(), const BGeneric());
+    fooGeneric(y: const BGeneric(), const BGeneric());
   });
   runAndCheckForTypeArgument(int, () {
-      fooGeneric(const BGeneric<int>(), y: const BGeneric<List<int>>());
+    fooGeneric(const BGeneric<int>(), y: const BGeneric<List<int>>());
   });
   runAndCheckForTypeArgument(String, () {
-      fooGeneric(y: const BGeneric<List<String>>(), const BGeneric<String>());
+    fooGeneric(y: const BGeneric<List<String>>(), const BGeneric<String>());
   });
 
   runAndCheckForTypeArgument(double, () {
-      fooFunction(42, y: bar);
+    fooFunction(42, y: bar);
   });
   runAndCheckForTypeArgument(double, () {
-      fooFunction(y: bar, 42);
+    fooFunction(y: bar, 42);
   });
 
   runAndCheckForTypeArgument(String, () {
-      fooFunctionGeneric(42, y: (String x) {});
+    fooFunctionGeneric(42, y: (String x) {});
   });
   runAndCheckForTypeArgument(num, () {
-      fooFunctionGeneric(y: (num x) {}, 42);
+    fooFunctionGeneric(y: (num x) {}, 42);
   });
 }
diff --git a/tests/language/super/call3_test.dart b/tests/language/super/call3_test.dart
index 7c43edf..a3b810d 100644
--- a/tests/language/super/call3_test.dart
+++ b/tests/language/super/call3_test.dart
@@ -7,8 +7,7 @@
 import "package:expect/expect.dart";
 
 class A {
-  A(
-    this.x
+  A(this.x
 //  ^^^^^^
 // [analyzer] COMPILE_TIME_ERROR.INITIALIZING_FORMAL_FOR_NON_EXISTENT_FIELD
 //       ^
@@ -25,19 +24,17 @@
 class B2 extends A {
   B2();
 //^^
-// [analyzer] COMPILE_TIME_ERROR.NO_DEFAULT_SUPER_CONSTRUCTOR
+// [analyzer] COMPILE_TIME_ERROR.IMPLICIT_SUPER_INITIALIZER_MISSING_ARGUMENTS
 // [cfe] The superclass, 'A', has no unnamed constructor that takes no arguments.
   B2.named() : this.x = 499;
 //^^^^^^^^
-// [analyzer] COMPILE_TIME_ERROR.NO_DEFAULT_SUPER_CONSTRUCTOR
+// [analyzer] COMPILE_TIME_ERROR.IMPLICIT_SUPER_INITIALIZER_MISSING_ARGUMENTS
 // [cfe] The superclass, 'A', has no unnamed constructor that takes no arguments.
   var x;
 }
 
 class C {
-  C
-  .named
-  ();
+  C.named();
   final foo = 499;
 }
 
diff --git a/tools/VERSION b/tools/VERSION
index 46a6247..d182bf2 100644
--- a/tools/VERSION
+++ b/tools/VERSION
@@ -27,5 +27,5 @@
 MAJOR 2
 MINOR 17
 PATCH 0
-PRERELEASE 171
+PRERELEASE 172
 PRERELEASE_PATCH 0
\ No newline at end of file
diff --git a/tools/experimental_features.yaml b/tools/experimental_features.yaml
index 3483305..0fd686d 100644
--- a/tools/experimental_features.yaml
+++ b/tools/experimental_features.yaml
@@ -122,15 +122,6 @@
   const-functions:
     help: "Allow more of the Dart language to be executed in const expressions."
 
-  enhanced-enums:
-    help: "Enhanced Enums"
-
-  named-arguments-anywhere:
-    help: "Named Arguments Anywhere"
-
-  super-parameters:
-    help: "Super-Initializer Parameters"
-
   macros:
     help: "Static meta-programming"
 
@@ -225,3 +216,45 @@
         c();
       }
     expired: true
+
+  enhanced-enums:
+    help: "Enhanced Enums"
+    enabledIn: '2.17.0'
+    validation: |
+      enum T {
+        t();
+        void test() {
+          print('feature enabled');
+        }
+      }
+      void main() {
+        T.t.test();
+      }
+
+  named-arguments-anywhere:
+    help: "Named Arguments Anywhere"
+    enabledIn: '2.17.0'
+    validation: |
+      void test(String msg, {bool enabled : false}) {
+        if (enabled) {
+          print(msg);
+        }
+      }
+      void main() {
+        test(enabled : true, 'feature enabled');
+      }
+
+  super-parameters:
+    help: "Super-Initializer Parameters"
+    enabledIn: '2.17.0'
+    validation: |
+      class B {
+        final String foo;
+         B(this.foo);
+      }
+      class C extends B {
+        C(super.foo);
+      }
+      void main(){
+        print(C('feature enabled').foo);
+      }