Fix for issue 4921: ad the generic type info to a List when we create it.

lib/compiler/implementation/ssa/builder.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.
 
 class Interceptors {
   Compiler compiler;
   Interceptors(Compiler this.compiler);
 
   SourceString mapOperatorToMethodName(Operator op) {
     String name = op.source.stringValue;
@@ skipping 1215 matching lines @@
       constructorArguments.add(
           potentiallyCheckType(fieldValues[member], member));
     });
 
     HForeignNew newObject = new HForeignNew(classElement, constructorArguments);
     add(newObject);
 
     // If the class has type variables, create the runtime type
     // information with the type parameters provided.
     if (!classElement.typeVariables.isEmpty()) {
-      List<String> typeVariables = <String>[];
       List<HInstruction> rtiInputs = <HInstruction>[];
       classElement.typeVariables.forEach((TypeVariableType typeVariable) {
-        typeVariables.add("'$typeVariable': #");
         rtiInputs.add(localsHandler.directLocals[typeVariable.element]);
       });
-      String jsCode = '{ ${Strings.join(typeVariables, ', ')} }';
-      HInstruction typeInfo = new HForeign(new LiteralDartString(jsCode),
-                                           new LiteralDartString('Object'),
-                                           rtiInputs);
-      add(typeInfo);
-      Element typeInfoSetterElement = interceptors.getSetRuntimeTypeInfo();
-      HInstruction typeInfoSetter = new HStatic(typeInfoSetterElement);
-      add(typeInfoSetter);
-      add(new HInvokeStatic(
-          <HInstruction>[typeInfoSetter, newObject, typeInfo]));
+      callSetRuntimeTypeInfo(classElement, rtiInputs, newObject);
     }
 
     // Generate calls to the constructor bodies.
     for (int index = constructors.length - 1; index >= 0; index--) {
       FunctionElement constructor = constructors[index];
       ConstructorBodyElement body = getConstructorBody(constructor);
       if (body === null) continue;
       List bodyCallInputs = <HInstruction>[];
       bodyCallInputs.add(newObject);
       int arity = body.functionSignature.parameterCount;
@@ skipping 1358 matching lines @@
         compiler.cancel('Unimplemented unresolved type variable',
                         node: currentNode);
       }
     } else {
       // The type variable is a type (e.g. int).
       return graph.addConstantString(
           new LiteralDartString('$argument'), currentNode, constantSystem);
     }
   }
 
+  void handleListConstructor(InterfaceType type,
+                             Node currentNode,
+                             HInstruction newObject) {
+    if (type.arguments.isEmpty()) return;
+    List<HInstruction> inputs = <HInstruction>[];
+    type.arguments.forEach((DartType argument) {
+      inputs.add(analyzeTypeArgument(argument, currentNode));
+    });
+    callSetRuntimeTypeInfo(type.element, inputs, newObject);
+  }
+
+  void callSetRuntimeTypeInfo(ClassElement element,
+                              List<HInstruction> inputs,
+                              HInstruction newObject) {
+    List<String> typeVariables = <String>[];
+    element.typeVariables.forEach((TypeVariableType typeVariable) {
+      typeVariables.add("'$typeVariable': #");
+    });
+
+    String jsCode = '{ ${Strings.join(typeVariables, ', ')} }';
+    HInstruction typeInfo = new HForeign(new LiteralDartString(jsCode),
+                                         new LiteralDartString('Object'),
+                                         inputs);
+    add(typeInfo);
+    Element typeInfoSetterElement = interceptors.getSetRuntimeTypeInfo();
+    HInstruction typeInfoSetter = new HStatic(typeInfoSetterElement);
+    add(typeInfoSetter);
+    add(new HInvokeStatic(<HInstruction>[typeInfoSetter, newObject, typeInfo]));
+  }
+
   visitNewSend(Send node) {
+    bool isListConstructor = false;
     computeType(element) {
       Element originalElement = elements[node];
       if (originalElement.getEnclosingClass() === compiler.listClass) {
+        isListConstructor = true;
         if (node.arguments.isEmpty()) {
           return HType.EXTENDABLE_ARRAY;
         } else {
           return HType.MUTABLE_ARRAY;
         }
       } else if (element.isGenerativeConstructor()) {
         ClassElement cls = element.getEnclosingClass();
         return new HBoundedType.exact(cls.type);
       } else {
         return HType.UNKNOWN;
@@ skipping 24 matching lines @@
       compiler.internalError("malformed send in new expression");
     }
     InterfaceType type = elements.getType(annotation);
     type.arguments.forEach((DartType argument) {
       inputs.add(analyzeTypeArgument(argument, node));
     });
 
     HType elementType = computeType(constructor);
     HInstruction newInstance = new HInvokeStatic(inputs, elementType);
     pushWithPosition(newInstance, node);
+
+    // The List constructor forwards to a Dart static method that does
+    // not know about the type argument. Therefore we special case
+    // this constructor to have the setRuntimeTypeInfo called where
+    // the 'new' is done.
+    if (isListConstructor) {
+      handleListConstructor(type, node, newInstance);
+    }
   }
 
   visitStaticSend(Send node) {
     Selector selector = elements.getSelector(node);
     Element element = elements[node];
     if (element.isErroneous()) {
       generateThrowNoSuchMethod(node, getTargetName(element), node.arguments);
       return;
     }
     if (element === compiler.assertMethod && !compiler.enableUserAssertions) {
@@ skipping 1452 matching lines @@
           new HSubGraphBlockInformation(elseBranch.graph));
 
     HBasicBlock conditionStartBlock = conditionBranch.block;
     conditionStartBlock.setBlockFlow(info, joinBlock);
     SubGraph conditionGraph = conditionBranch.graph;
     HIf branch = conditionGraph.end.last;
     assert(branch is HIf);
     branch.blockInformation = conditionStartBlock.blockFlow;
   }
 }