Ensure supertypes are loaded safely.

dart/lib/compiler/implementation/compiler.dart

 // Copyright (c) 2012, 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.
 
 
 /**
  * If true, print a warning for each method that was resolved, but not
  * compiled.
  */
 final bool REPORT_EXCESS_RESOLUTION = false;
@@ skipping 130 matching lines @@
   Stopwatch progress;
 
   static final int PHASE_SCANNING = 0;
   static final int PHASE_RESOLVING = 1;
   static final int PHASE_COMPILING = 2;
   static final int PHASE_RECOMPILING = 3;
   int phase;
 
   bool compilationFailed = false;
 
+  bool hasCrashed = false;
+
   Compiler([this.tracer = const Tracer(),
             this.enableTypeAssertions = false,
             this.enableUserAssertions = false,
             bool emitJavascript = true,
             validateUnparse = false,
             generateSourceMap = true])
       : libraries = new Map<String, LibraryElement>(),
         world = new World(),
         progress = new Stopwatch.start() {
     namer = new Namer(this);
@@ skipping 35 matching lines @@
                      [Node node, Token token, HInstruction instruction,
                       Element element]) {
     cancel('Internal error: $message', node, token, instruction, element);
   }
 
   void internalErrorOnElement(Element element, String message) {
     internalError(message, element: element);
   }
 
   void unhandledExceptionOnElement(Element element) {
+    if (hasCrashed) return;
+    hasCrashed = true;
     reportDiagnostic(spanFromElement(element),
                      MessageKind.COMPILER_CRASHED.error().toString(),
                      api.Diagnostic.CRASH);
     // TODO(ahe): Obtain the build ID.
     var buildId = 'build number could not be determined';
     print(MessageKind.PLEASE_REPORT_THE_CRASH.message([buildId]));
   }
 
   void cancel([String reason, Node node, Token token,
                HInstruction instruction, Element element]) {
@@ skipping 540 matching lines @@
       codegenWorld.addGeneratedCode(work, codeBuffer);
       return codeBuffer.toString();
     }
   }
 
   void registerInstantiatedClass(ClassElement cls) {
     enqueuer.resolution.registerInstantiatedClass(cls);
     enqueuer.codegen.registerInstantiatedClass(cls);
   }
 
-  void resolveClass(ClassElement element) {
-    withCurrentElement(element, () => resolver.resolveClass(element));
-  }
-
   Type resolveTypeAnnotation(Element element, TypeAnnotation annotation) {
     return resolver.resolveTypeAnnotation(element, annotation);
   }
 
   FunctionSignature resolveSignature(FunctionElement element) {
     return withCurrentElement(element,
                               () => resolver.resolveSignature(element));
   }
 
   FunctionSignature resolveFunctionExpression(Element element,
@@ skipping 166 matching lines @@
     final endOffset = end.charOffset + end.slowCharCount;
 
     // [begin] and [end] might be the same for the same empty token. This
     // happens for instance when scanning '$$'.
     assert(endOffset >= beginOffset);
     return f(beginOffset, endOffset);
   }
 
   String toString() => 'SourceSpan($uri, $begin, $end)';
 }