diff --git a/pkg/front_end/lib/src/fasta/kernel/inference_visitor.dart b/pkg/front_end/lib/src/fasta/kernel/inference_visitor.dart
index 4549c6b..d52aaff 100644
--- a/pkg/front_end/lib/src/fasta/kernel/inference_visitor.dart
+++ b/pkg/front_end/lib/src/fasta/kernel/inference_visitor.dart
@@ -48,18 +48,6 @@
 
   Class? mapEntryClass;
 
-  // Stores the offset of the map entry found by inferMapEntry.
-  int? mapEntryOffset = null;
-
-  // Stores the offset of the map spread found by inferMapEntry.
-  int? mapSpreadOffset = null;
-
-  // Stores the offset of the iterable spread found by inferMapEntry.
-  int? iterableSpreadOffset = null;
-
-  // Stores the type of the iterable spread found by inferMapEntry.
-  DartType? iterableSpreadType = null;
-
   InferenceVisitor(this.inferrer);
 
   /// Computes uri and offset for [node] for internal errors in a way that is
@@ -2174,7 +2162,8 @@
       Map<TreeNode, DartType> inferredSpreadTypes,
       Map<Expression, DartType> inferredConditionTypes,
       bool inferenceNeeded,
-      bool typeChecksNeeded) {
+      bool typeChecksNeeded,
+      _MapLiteralEntryOffsets offsets) {
     if (entry is SpreadMapEntry) {
       ExpressionInferenceResult spreadResult = inferrer.inferExpression(
           entry.expression, spreadContext, inferenceNeeded || typeChecksNeeded,
@@ -2230,7 +2219,7 @@
 
             // Don't report the error here, it might be an ambiguous Set.  The
             // error is reported in checkMapEntry if it's disambiguated as map.
-            iterableSpreadType = spreadType;
+            offsets.iterableSpreadType = spreadType;
           } else {
             Expression receiver = entry.expression;
             Expression problem = inferrer.helper.buildProblem(
@@ -2389,10 +2378,10 @@
           inferrer.coreTypes.iterableRawType(inferrer.libraryBuilder.nullable),
           SubtypeCheckMode.withNullabilities);
       if (isMap && !isIterable) {
-        mapSpreadOffset = entry.fileOffset;
+        offsets.mapSpreadOffset = entry.fileOffset;
       }
       if (!isMap && isIterable) {
-        iterableSpreadOffset = entry.expression.fileOffset;
+        offsets.iterableSpreadOffset = entry.expression.fileOffset;
       }
 
       return replacement;
@@ -2421,9 +2410,9 @@
           inferredSpreadTypes,
           inferredConditionTypes,
           inferenceNeeded,
-          typeChecksNeeded);
+          typeChecksNeeded,
+          offsets);
       entry.then = then..parent = entry;
-      MapLiteralEntry otherwise;
       if (entry.otherwise != null) {
         inferrer.flowAnalysis.ifStatement_elseBegin();
         // We need to modify the actual types added in the recursive call to
@@ -2431,7 +2420,7 @@
         DartType? actualValueType = actualTypes.removeLast();
         DartType? actualKeyType = actualTypes.removeLast();
         DartType actualTypeForSet = actualTypesForSet.removeLast();
-        otherwise = inferMapEntry(
+        MapLiteralEntry otherwise = inferMapEntry(
             entry.otherwise!,
             entry,
             inferredKeyType,
@@ -2442,7 +2431,8 @@
             inferredSpreadTypes,
             inferredConditionTypes,
             inferenceNeeded,
-            typeChecksNeeded);
+            typeChecksNeeded,
+            offsets);
         int length = actualTypes.length;
         actualTypes[length - 2] = inferrer.typeSchemaEnvironment
             .getStandardUpperBound(actualKeyType, actualTypes[length - 2],
@@ -2524,7 +2514,8 @@
           inferredSpreadTypes,
           inferredConditionTypes,
           inferenceNeeded,
-          typeChecksNeeded);
+          typeChecksNeeded,
+          offsets);
       entry.body = body..parent = entry;
       inferrer.flowAnalysis.for_updaterBegin();
       for (int index = 0; index < entry.updates.length; index++) {
@@ -2576,7 +2567,8 @@
           inferredSpreadTypes,
           inferredConditionTypes,
           inferenceNeeded,
-          typeChecksNeeded);
+          typeChecksNeeded,
+          offsets);
       entry.body = body..parent = entry;
       // This is matched by the call to [forEach_bodyBegin] in
       // [handleForInWithoutVariable] or [handleForInDeclaringVariable].
@@ -2603,7 +2595,7 @@
       actualTypes.add(valueResult.inferredType);
       // Use 'dynamic' for error recovery.
       actualTypesForSet.add(const DynamicType());
-      mapEntryOffset = entry.fileOffset;
+      offsets.mapEntryOffset = entry.fileOffset;
       return entry;
     }
   }
@@ -2613,18 +2605,19 @@
       DartType keyType,
       DartType valueType,
       Map<TreeNode, DartType> inferredSpreadTypes,
-      Map<Expression, DartType> inferredConditionTypes) {
+      Map<Expression, DartType> inferredConditionTypes,
+      _MapLiteralEntryOffsets offsets) {
     // It's disambiguated as a map literal.
     MapLiteralEntry replacement = entry;
-    if (iterableSpreadOffset != null) {
+    if (offsets.iterableSpreadOffset != null) {
       replacement = new MapLiteralEntry(
           inferrer.helper.buildProblem(
               templateSpreadMapEntryTypeMismatch.withArguments(
-                  iterableSpreadType!, inferrer.isNonNullableByDefault),
-              iterableSpreadOffset!,
+                  offsets.iterableSpreadType!, inferrer.isNonNullableByDefault),
+              offsets.iterableSpreadOffset!,
               1),
           new NullLiteral())
-        ..fileOffset = iterableSpreadOffset!;
+        ..fileOffset = offsets.iterableSpreadOffset!;
     }
     if (entry is SpreadMapEntry) {
       DartType? spreadType = inferredSpreadTypes[entry.expression];
@@ -2638,11 +2631,11 @@
       }
     } else if (entry is IfMapEntry) {
       MapLiteralEntry then = checkMapEntry(entry.then, keyType, valueType,
-          inferredSpreadTypes, inferredConditionTypes);
+          inferredSpreadTypes, inferredConditionTypes, offsets);
       entry.then = then..parent = entry;
       if (entry.otherwise != null) {
         MapLiteralEntry otherwise = checkMapEntry(entry.otherwise!, keyType,
-            valueType, inferredSpreadTypes, inferredConditionTypes);
+            valueType, inferredSpreadTypes, inferredConditionTypes, offsets);
         entry.otherwise = otherwise..parent = entry;
       }
     } else if (entry is ForMapEntry) {
@@ -2655,11 +2648,11 @@
         entry.condition = condition..parent = entry;
       }
       MapLiteralEntry body = checkMapEntry(entry.body, keyType, valueType,
-          inferredSpreadTypes, inferredConditionTypes);
+          inferredSpreadTypes, inferredConditionTypes, offsets);
       entry.body = body..parent = entry;
     } else if (entry is ForInMapEntry) {
       MapLiteralEntry body = checkMapEntry(entry.body, keyType, valueType,
-          inferredSpreadTypes, inferredConditionTypes);
+          inferredSpreadTypes, inferredConditionTypes, offsets);
       entry.body = body..parent = entry;
     } else {
       // Do nothing.  Assignability checks are done during type inference.
@@ -2735,11 +2728,8 @@
     bool hasMapEntry = false;
     bool hasMapSpread = false;
     bool hasIterableSpread = false;
+    _MapLiteralEntryOffsets offsets = new _MapLiteralEntryOffsets();
     if (inferenceNeeded || typeChecksNeeded) {
-      mapEntryOffset = null;
-      mapSpreadOffset = null;
-      iterableSpreadOffset = null;
-      iterableSpreadType = null;
       DartType spreadTypeContext = const UnknownType();
       if (typeContextIsIterable && !typeContextIsMap) {
         spreadTypeContext = inferrer.typeSchemaEnvironment.getTypeAsInstanceOf(
@@ -2754,9 +2744,8 @@
             <DartType>[inferredKeyType, inferredValueType]);
       }
       for (int index = 0; index < node.entries.length; ++index) {
-        MapLiteralEntry entry = node.entries[index];
-        entry = inferMapEntry(
-            entry,
+        MapLiteralEntry entry = inferMapEntry(
+            node.entries[index],
             node,
             inferredKeyType,
             inferredValueType,
@@ -2766,16 +2755,17 @@
             inferredSpreadTypes!,
             inferredConditionTypes!,
             inferenceNeeded,
-            typeChecksNeeded);
+            typeChecksNeeded,
+            offsets);
         node.entries[index] = entry..parent = node;
         if (inferenceNeeded) {
           formalTypes!.add(mapType.typeArguments[0]);
           formalTypes.add(mapType.typeArguments[1]);
         }
       }
-      hasMapEntry = mapEntryOffset != null;
-      hasMapSpread = mapSpreadOffset != null;
-      hasIterableSpread = iterableSpreadOffset != null;
+      hasMapEntry = offsets.mapEntryOffset != null;
+      hasMapSpread = offsets.mapSpreadOffset != null;
+      hasIterableSpread = offsets.iterableSpreadOffset != null;
     }
     if (inferenceNeeded) {
       bool canBeSet = !hasMapSpread && !hasMapEntry && !typeContextIsMap;
@@ -2880,8 +2870,13 @@
     }
     if (typeChecksNeeded) {
       for (int index = 0; index < node.entries.length; ++index) {
-        MapLiteralEntry entry = checkMapEntry(node.entries[index], node.keyType,
-            node.valueType, inferredSpreadTypes!, inferredConditionTypes!);
+        MapLiteralEntry entry = checkMapEntry(
+            node.entries[index],
+            node.keyType,
+            node.valueType,
+            inferredSpreadTypes!,
+            inferredConditionTypes!,
+            offsets);
         node.entries[index] = entry..parent = node;
       }
     }
@@ -7348,3 +7343,18 @@
 
   _UriOffset(this.uri, this.fileOffset);
 }
+
+/// Offset and type information collection in [InferenceVisitor.inferMapEntry].
+class _MapLiteralEntryOffsets {
+  // Stores the offset of the map entry found by inferMapEntry.
+  int? mapEntryOffset;
+
+  // Stores the offset of the map spread found by inferMapEntry.
+  int? mapSpreadOffset;
+
+  // Stores the offset of the iterable spread found by inferMapEntry.
+  int? iterableSpreadOffset;
+
+  // Stores the type of the iterable spread found by inferMapEntry.
+  DartType? iterableSpreadType;
+}
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 43b3074..00b7e5e 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
@@ -47,6 +47,7 @@
         noLength;
 import '../scope.dart';
 import '../source/source_class_builder.dart';
+import '../source/source_enum_builder.dart';
 import '../source/source_library_builder.dart' show SourceLibraryBuilder;
 import '../source/source_loader.dart' show SourceLoader;
 import '../source/source_member_builder.dart';
@@ -249,6 +250,15 @@
   }
 
   @override
+  VariableDeclaration getFormalParameter(int index) {
+    if (parent is SourceEnumBuilder) {
+      return formals![index + 2].variable!;
+    } else {
+      return super.getFormalParameter(index);
+    }
+  }
+
+  @override
   void inferTypes(ClassHierarchyBase hierarchy) {
     inferFormalTypes(hierarchy);
   }
diff --git a/pkg/front_end/testcases/enhanced_enums/named_arguments.dart.strong.expect b/pkg/front_end/testcases/enhanced_enums/named_arguments.dart.strong.expect
index beb0d94..c6b555c 100644
--- a/pkg/front_end/testcases/enhanced_enums/named_arguments.dart.strong.expect
+++ b/pkg/front_end/testcases/enhanced_enums/named_arguments.dart.strong.expect
@@ -8,7 +8,7 @@
   final field core::int bar;
   static const field self::E0 one = #C4;
   static const field self::E0 two = #C7;
-  const constructor •(core::int #index, core::String #name = #C9, core::int foo, {required core::int bar = #C9}) → self::E0
+  const constructor •(core::int #index, core::String #name, core::int foo, {required core::int bar = #C9}) → self::E0
     : self::E0::foo = foo, self::E0::bar = bar, super core::_Enum::•(#index, #name)
     ;
   method toString() → core::String
@@ -19,7 +19,7 @@
   final field self::E1::X% foo;
   static const field self::E1<core::String> one = #C11;
   static const field self::E1<core::int> two = #C12;
-  const constructor •(core::int #index = #C9, core::String #name, {required self::E1::X% foo = #C9}) → self::E1<self::E1::X%>
+  const constructor •(core::int #index, core::String #name, {required self::E1::X% foo = #C9}) → self::E1<self::E1::X%>
     : self::E1::foo = foo, super core::_Enum::•(#index, #name)
     ;
   method toString() → core::String
@@ -33,7 +33,7 @@
   static const field self::E2<core::int, core::String, core::double> one = #C15;
   static const field self::E2<core::String, core::int, core::double> two = #C17;
   static const field self::E2<core::double, core::bool, dynamic> three = #C21;
-  const constructor •(core::int #index, core::String #name = #C9, self::E2::X% foo, {required self::E2::Y% bar = #C9, has-declared-initializer self::E2::Z? baz = #C9}) → self::E2<self::E2::X%, self::E2::Y%, self::E2::Z%>
+  const constructor •(core::int #index, core::String #name, self::E2::X% foo, {required self::E2::Y% bar = #C9, has-declared-initializer self::E2::Z? baz = #C9}) → self::E2<self::E2::X%, self::E2::Y%, self::E2::Z%>
     : self::E2::foo = foo, self::E2::bar = bar, self::E2::baz = baz, super core::_Enum::•(#index, #name)
     ;
   method toString() → core::String
diff --git a/pkg/front_end/testcases/enhanced_enums/named_arguments.dart.strong.transformed.expect b/pkg/front_end/testcases/enhanced_enums/named_arguments.dart.strong.transformed.expect
index beb0d94..c6b555c 100644
--- a/pkg/front_end/testcases/enhanced_enums/named_arguments.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/enhanced_enums/named_arguments.dart.strong.transformed.expect
@@ -8,7 +8,7 @@
   final field core::int bar;
   static const field self::E0 one = #C4;
   static const field self::E0 two = #C7;
-  const constructor •(core::int #index, core::String #name = #C9, core::int foo, {required core::int bar = #C9}) → self::E0
+  const constructor •(core::int #index, core::String #name, core::int foo, {required core::int bar = #C9}) → self::E0
     : self::E0::foo = foo, self::E0::bar = bar, super core::_Enum::•(#index, #name)
     ;
   method toString() → core::String
@@ -19,7 +19,7 @@
   final field self::E1::X% foo;
   static const field self::E1<core::String> one = #C11;
   static const field self::E1<core::int> two = #C12;
-  const constructor •(core::int #index = #C9, core::String #name, {required self::E1::X% foo = #C9}) → self::E1<self::E1::X%>
+  const constructor •(core::int #index, core::String #name, {required self::E1::X% foo = #C9}) → self::E1<self::E1::X%>
     : self::E1::foo = foo, super core::_Enum::•(#index, #name)
     ;
   method toString() → core::String
@@ -33,7 +33,7 @@
   static const field self::E2<core::int, core::String, core::double> one = #C15;
   static const field self::E2<core::String, core::int, core::double> two = #C17;
   static const field self::E2<core::double, core::bool, dynamic> three = #C21;
-  const constructor •(core::int #index, core::String #name = #C9, self::E2::X% foo, {required self::E2::Y% bar = #C9, has-declared-initializer self::E2::Z? baz = #C9}) → self::E2<self::E2::X%, self::E2::Y%, self::E2::Z%>
+  const constructor •(core::int #index, core::String #name, self::E2::X% foo, {required self::E2::Y% bar = #C9, has-declared-initializer self::E2::Z? baz = #C9}) → self::E2<self::E2::X%, self::E2::Y%, self::E2::Z%>
     : self::E2::foo = foo, self::E2::bar = bar, self::E2::baz = baz, super core::_Enum::•(#index, #name)
     ;
   method toString() → core::String
diff --git a/pkg/front_end/testcases/enhanced_enums/named_arguments.dart.weak.expect b/pkg/front_end/testcases/enhanced_enums/named_arguments.dart.weak.expect
index 67cb833..04b9df2 100644
--- a/pkg/front_end/testcases/enhanced_enums/named_arguments.dart.weak.expect
+++ b/pkg/front_end/testcases/enhanced_enums/named_arguments.dart.weak.expect
@@ -8,7 +8,7 @@
   final field core::int bar;
   static const field self::E0 one = #C4;
   static const field self::E0 two = #C7;
-  const constructor •(core::int #index, core::String #name = #C9, core::int foo, {required core::int bar = #C9}) → self::E0
+  const constructor •(core::int #index, core::String #name, core::int foo, {required core::int bar = #C9}) → self::E0
     : self::E0::foo = foo, self::E0::bar = bar, super core::_Enum::•(#index, #name)
     ;
   method toString() → core::String
@@ -19,7 +19,7 @@
   final field self::E1::X% foo;
   static const field self::E1<core::String> one = #C11;
   static const field self::E1<core::int> two = #C12;
-  const constructor •(core::int #index = #C9, core::String #name, {required self::E1::X% foo = #C9}) → self::E1<self::E1::X%>
+  const constructor •(core::int #index, core::String #name, {required self::E1::X% foo = #C9}) → self::E1<self::E1::X%>
     : self::E1::foo = foo, super core::_Enum::•(#index, #name)
     ;
   method toString() → core::String
@@ -33,7 +33,7 @@
   static const field self::E2<core::int, core::String, core::double> one = #C15;
   static const field self::E2<core::String, core::int, core::double> two = #C17;
   static const field self::E2<core::double, core::bool, dynamic> three = #C21;
-  const constructor •(core::int #index, core::String #name = #C9, self::E2::X% foo, {required self::E2::Y% bar = #C9, has-declared-initializer self::E2::Z? baz = #C9}) → self::E2<self::E2::X%, self::E2::Y%, self::E2::Z%>
+  const constructor •(core::int #index, core::String #name, self::E2::X% foo, {required self::E2::Y% bar = #C9, has-declared-initializer self::E2::Z? baz = #C9}) → self::E2<self::E2::X%, self::E2::Y%, self::E2::Z%>
     : self::E2::foo = foo, self::E2::bar = bar, self::E2::baz = baz, super core::_Enum::•(#index, #name)
     ;
   method toString() → core::String
diff --git a/pkg/front_end/testcases/enhanced_enums/named_arguments.dart.weak.modular.expect b/pkg/front_end/testcases/enhanced_enums/named_arguments.dart.weak.modular.expect
index 67cb833..04b9df2 100644
--- a/pkg/front_end/testcases/enhanced_enums/named_arguments.dart.weak.modular.expect
+++ b/pkg/front_end/testcases/enhanced_enums/named_arguments.dart.weak.modular.expect
@@ -8,7 +8,7 @@
   final field core::int bar;
   static const field self::E0 one = #C4;
   static const field self::E0 two = #C7;
-  const constructor •(core::int #index, core::String #name = #C9, core::int foo, {required core::int bar = #C9}) → self::E0
+  const constructor •(core::int #index, core::String #name, core::int foo, {required core::int bar = #C9}) → self::E0
     : self::E0::foo = foo, self::E0::bar = bar, super core::_Enum::•(#index, #name)
     ;
   method toString() → core::String
@@ -19,7 +19,7 @@
   final field self::E1::X% foo;
   static const field self::E1<core::String> one = #C11;
   static const field self::E1<core::int> two = #C12;
-  const constructor •(core::int #index = #C9, core::String #name, {required self::E1::X% foo = #C9}) → self::E1<self::E1::X%>
+  const constructor •(core::int #index, core::String #name, {required self::E1::X% foo = #C9}) → self::E1<self::E1::X%>
     : self::E1::foo = foo, super core::_Enum::•(#index, #name)
     ;
   method toString() → core::String
@@ -33,7 +33,7 @@
   static const field self::E2<core::int, core::String, core::double> one = #C15;
   static const field self::E2<core::String, core::int, core::double> two = #C17;
   static const field self::E2<core::double, core::bool, dynamic> three = #C21;
-  const constructor •(core::int #index, core::String #name = #C9, self::E2::X% foo, {required self::E2::Y% bar = #C9, has-declared-initializer self::E2::Z? baz = #C9}) → self::E2<self::E2::X%, self::E2::Y%, self::E2::Z%>
+  const constructor •(core::int #index, core::String #name, self::E2::X% foo, {required self::E2::Y% bar = #C9, has-declared-initializer self::E2::Z? baz = #C9}) → self::E2<self::E2::X%, self::E2::Y%, self::E2::Z%>
     : self::E2::foo = foo, self::E2::bar = bar, self::E2::baz = baz, super core::_Enum::•(#index, #name)
     ;
   method toString() → core::String
diff --git a/pkg/front_end/testcases/enhanced_enums/named_arguments.dart.weak.transformed.expect b/pkg/front_end/testcases/enhanced_enums/named_arguments.dart.weak.transformed.expect
index 67cb833..04b9df2 100644
--- a/pkg/front_end/testcases/enhanced_enums/named_arguments.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/enhanced_enums/named_arguments.dart.weak.transformed.expect
@@ -8,7 +8,7 @@
   final field core::int bar;
   static const field self::E0 one = #C4;
   static const field self::E0 two = #C7;
-  const constructor •(core::int #index, core::String #name = #C9, core::int foo, {required core::int bar = #C9}) → self::E0
+  const constructor •(core::int #index, core::String #name, core::int foo, {required core::int bar = #C9}) → self::E0
     : self::E0::foo = foo, self::E0::bar = bar, super core::_Enum::•(#index, #name)
     ;
   method toString() → core::String
@@ -19,7 +19,7 @@
   final field self::E1::X% foo;
   static const field self::E1<core::String> one = #C11;
   static const field self::E1<core::int> two = #C12;
-  const constructor •(core::int #index = #C9, core::String #name, {required self::E1::X% foo = #C9}) → self::E1<self::E1::X%>
+  const constructor •(core::int #index, core::String #name, {required self::E1::X% foo = #C9}) → self::E1<self::E1::X%>
     : self::E1::foo = foo, super core::_Enum::•(#index, #name)
     ;
   method toString() → core::String
@@ -33,7 +33,7 @@
   static const field self::E2<core::int, core::String, core::double> one = #C15;
   static const field self::E2<core::String, core::int, core::double> two = #C17;
   static const field self::E2<core::double, core::bool, dynamic> three = #C21;
-  const constructor •(core::int #index, core::String #name = #C9, self::E2::X% foo, {required self::E2::Y% bar = #C9, has-declared-initializer self::E2::Z? baz = #C9}) → self::E2<self::E2::X%, self::E2::Y%, self::E2::Z%>
+  const constructor •(core::int #index, core::String #name, self::E2::X% foo, {required self::E2::Y% bar = #C9, has-declared-initializer self::E2::Z? baz = #C9}) → self::E2<self::E2::X%, self::E2::Y%, self::E2::Z%>
     : self::E2::foo = foo, self::E2::bar = bar, self::E2::baz = baz, super core::_Enum::•(#index, #name)
     ;
   method toString() → core::String
diff --git a/pkg/front_end/testcases/general/issue49216.dart b/pkg/front_end/testcases/general/issue49216.dart
new file mode 100644
index 0000000..1668ed4
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue49216.dart
@@ -0,0 +1,12 @@
+// Copyright (c) 2022, the Dart project authors.  Please see the AUTHORS file
+// 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.
+
+enum E {
+  foo;
+
+  const E([int x = 0, String y = "", num? z]);
+  const E.named(int x, {String y = "", bool b = false, String? z, bool? t});
+}
+
+main() {}
diff --git a/pkg/front_end/testcases/general/issue49216.dart.textual_outline.expect b/pkg/front_end/testcases/general/issue49216.dart.textual_outline.expect
new file mode 100644
index 0000000..d4f3d20
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue49216.dart.textual_outline.expect
@@ -0,0 +1,8 @@
+enum E {
+  foo;
+
+  const E([int x = 0, String y = "", num? z]);
+  const E.named(int x, {String y = "", bool b = false, String? z, bool? t});
+}
+
+main() {}
diff --git a/pkg/front_end/testcases/general/issue49216.dart.textual_outline_modelled.expect b/pkg/front_end/testcases/general/issue49216.dart.textual_outline_modelled.expect
new file mode 100644
index 0000000..d4f3d20
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue49216.dart.textual_outline_modelled.expect
@@ -0,0 +1,8 @@
+enum E {
+  foo;
+
+  const E([int x = 0, String y = "", num? z]);
+  const E.named(int x, {String y = "", bool b = false, String? z, bool? t});
+}
+
+main() {}
diff --git a/pkg/front_end/testcases/general/issue49216.dart.weak.expect b/pkg/front_end/testcases/general/issue49216.dart.weak.expect
new file mode 100644
index 0000000..eee9a44
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue49216.dart.weak.expect
@@ -0,0 +1,34 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class E extends core::_Enum /*isEnum*/  {
+  static const field core::List<self::E> values = #C4;
+  static const field self::E foo = #C3;
+  const constructor •(core::int #index, core::String #name, [core::int x = #C1, core::String y = #C5, core::num? z = #C6]) → self::E
+    : super core::_Enum::•(#index, #name)
+    ;
+  const constructor named(core::int #index, core::String #name, core::int x, {core::String y = #C5, core::bool b = #C7, core::String? z = #C6, core::bool? t = #C6}) → self::E
+    : super core::_Enum::•(#index, #name)
+    ;
+  method toString() → core::String
+    return "E.${this.{core::_Enum::_name}{core::String}}";
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = 0
+  #C2 = "foo"
+  #C3 = self::E {index:#C1, _name:#C2}
+  #C4 = <self::E*>[#C3]
+  #C5 = ""
+  #C6 = null
+  #C7 = false
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///issue49216.dart:
+- E. (from org-dartlang-testcase:///issue49216.dart:8:9)
+- _Enum. (from org-dartlang-sdk:///sdk/lib/core/enum.dart:103:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/general/issue49216.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue49216.dart.weak.modular.expect
new file mode 100644
index 0000000..eee9a44
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue49216.dart.weak.modular.expect
@@ -0,0 +1,34 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class E extends core::_Enum /*isEnum*/  {
+  static const field core::List<self::E> values = #C4;
+  static const field self::E foo = #C3;
+  const constructor •(core::int #index, core::String #name, [core::int x = #C1, core::String y = #C5, core::num? z = #C6]) → self::E
+    : super core::_Enum::•(#index, #name)
+    ;
+  const constructor named(core::int #index, core::String #name, core::int x, {core::String y = #C5, core::bool b = #C7, core::String? z = #C6, core::bool? t = #C6}) → self::E
+    : super core::_Enum::•(#index, #name)
+    ;
+  method toString() → core::String
+    return "E.${this.{core::_Enum::_name}{core::String}}";
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = 0
+  #C2 = "foo"
+  #C3 = self::E {index:#C1, _name:#C2}
+  #C4 = <self::E*>[#C3]
+  #C5 = ""
+  #C6 = null
+  #C7 = false
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///issue49216.dart:
+- E. (from org-dartlang-testcase:///issue49216.dart:8:9)
+- _Enum. (from org-dartlang-sdk:///sdk/lib/core/enum.dart:103:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/general/issue49216.dart.weak.outline.expect b/pkg/front_end/testcases/general/issue49216.dart.weak.outline.expect
new file mode 100644
index 0000000..fa29e74
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue49216.dart.weak.outline.expect
@@ -0,0 +1,24 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class E extends core::_Enum /*isEnum*/  {
+  static const field core::List<self::E> values = const <self::E>[self::E::foo];
+  static const field self::E foo = const self::E::•(0, "foo");
+  const constructor •(core::int #index, core::String #name, [core::int x = 0, core::String y = "", core::num? z = null]) → self::E
+    : super core::_Enum::•(#index, #name)
+    ;
+  const constructor named(core::int #index, core::String #name, core::int x, {core::String y = "", core::bool b = false, core::String? z = null, core::bool? t = null}) → self::E
+    : super core::_Enum::•(#index, #name)
+    ;
+  method toString() → core::String
+    return "E.${this.{core::_Enum::_name}{core::String}}";
+}
+static method main() → dynamic
+  ;
+
+
+Extra constant evaluation status:
+Evaluated: ListLiteral @ org-dartlang-testcase:///issue49216.dart:5:6 -> ListConstant(const <E*>[const E{_Enum.index: 0, _Enum._name: "foo"}])
+Evaluated: ConstructorInvocation @ org-dartlang-testcase:///issue49216.dart:6:3 -> InstanceConstant(const E{_Enum.index: 0, _Enum._name: "foo"})
+Extra constant evaluation: evaluated: 9, effectively constant: 2
diff --git a/pkg/front_end/testcases/general/issue49216.dart.weak.transformed.expect b/pkg/front_end/testcases/general/issue49216.dart.weak.transformed.expect
new file mode 100644
index 0000000..eee9a44
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue49216.dart.weak.transformed.expect
@@ -0,0 +1,34 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class E extends core::_Enum /*isEnum*/  {
+  static const field core::List<self::E> values = #C4;
+  static const field self::E foo = #C3;
+  const constructor •(core::int #index, core::String #name, [core::int x = #C1, core::String y = #C5, core::num? z = #C6]) → self::E
+    : super core::_Enum::•(#index, #name)
+    ;
+  const constructor named(core::int #index, core::String #name, core::int x, {core::String y = #C5, core::bool b = #C7, core::String? z = #C6, core::bool? t = #C6}) → self::E
+    : super core::_Enum::•(#index, #name)
+    ;
+  method toString() → core::String
+    return "E.${this.{core::_Enum::_name}{core::String}}";
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = 0
+  #C2 = "foo"
+  #C3 = self::E {index:#C1, _name:#C2}
+  #C4 = <self::E*>[#C3]
+  #C5 = ""
+  #C6 = null
+  #C7 = false
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///issue49216.dart:
+- E. (from org-dartlang-testcase:///issue49216.dart:8:9)
+- _Enum. (from org-dartlang-sdk:///sdk/lib/core/enum.dart:103:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/tools/VERSION b/tools/VERSION
index a2f908b..8c03cac 100644
--- a/tools/VERSION
+++ b/tools/VERSION
@@ -27,5 +27,5 @@
 MAJOR 2
 MINOR 18
 PATCH 0
-PRERELEASE 183
+PRERELEASE 184
 PRERELEASE_PATCH 0
\ No newline at end of file