Finer grain control over specifying which variables have invalid constant initializers.

pkg/analyzer/lib/src/summary/resynthesize.dart

 // Copyright (c) 2015, 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.
 
 library summary_resynthesizer;
 
 import 'dart:collection';
 
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/token.dart';
@@ skipping 268 matching lines @@
   int doublePtr = 0;
   int stringPtr = 0;
   int refPtr = 0;
   final List<Expression> stack = <Expression>[];
 
   _ConstExprBuilder(this.resynthesizer, this.uc);
 
   Expression get expr => stack.single;
 
   Expression build() {
+    if (!uc.isValidConst) {
+      return AstFactory.identifier3(r'$$invalidConstExpr$$');
+    }
     for (UnlinkedConstOperation operation in uc.operations) {
       switch (operation) {
         case UnlinkedConstOperation.pushNull:
           _push(AstFactory.nullLiteral());
           break;
         // bool
         case UnlinkedConstOperation.pushFalse:
           _push(AstFactory.booleanLiteral(false));
           break;
         case UnlinkedConstOperation.pushTrue:
@@ skipping 153 matching lines @@
         case UnlinkedConstOperation.assignToRef:
         case UnlinkedConstOperation.assignToProperty:
         case UnlinkedConstOperation.assignToIndex:
         case UnlinkedConstOperation.extractIndex:
         case UnlinkedConstOperation.invokeMethod:
         case UnlinkedConstOperation.cascadeSectionBegin:
         case UnlinkedConstOperation.cascadeSectionEnd:
         case UnlinkedConstOperation.typeCast:
         case UnlinkedConstOperation.typeCheck:
         case UnlinkedConstOperation.throwException:
-          return AstFactory.identifier3(r'$notConst$');
+          throw new UnimplementedError(
+              'Unexpected $operation in a constant expression.');
       }
     }
     return stack.single;
   }
 
   List<Expression> _buildArguments() {
     List<Expression> arguments;
     {
       int numNamedArgs = uc.ints[intPtr++];
       int numPositionalArgs = uc.ints[intPtr++];
@@ skipping 2173 matching lines @@
   static String _getElementIdentifier(String name, ReferenceKind kind) {
     if (kind == ReferenceKind.topLevelPropertyAccessor ||
         kind == ReferenceKind.propertyAccessor) {
       if (!name.endsWith('=')) {
         return name + '?';
       }
     }
     return name;
   }
 }