Throw a dynamic type error instead of a CastError in a type cast with a

runtime/vm/flow_graph_builder.cc

Index: runtime/vm/flow_graph_builder.cc
===================================================================
--- runtime/vm/flow_graph_builder.cc	(revision 28684)
+++ runtime/vm/flow_graph_builder.cc	(working copy)
@@ -1298,7 +1298,7 @@
 void EffectGraphVisitor::BuildTypeCast(ComparisonNode* node) {
   ASSERT(Token::IsTypeCastOperator(node->kind()));
   const AbstractType& type = node->right()->AsTypeNode()->type();
-  ASSERT(type.IsFinalized());  // The type in a type cast may be malformed.
+  ASSERT(type.IsFinalized() && !type.IsMalformed() && !type.IsMalbounded());
   ValueGraphVisitor for_value(owner(), temp_index());
   node->left()->Visit(&for_value);
   const String& dst_name = String::ZoneHandle(
@@ -1315,54 +1315,47 @@
   ASSERT(Token::IsTypeCastOperator(node->kind()));
   ASSERT(!node->right()->AsTypeNode()->type().IsNull());
   const AbstractType& type = node->right()->AsTypeNode()->type();
-  ASSERT(type.IsFinalized());  // The type in a type cast may be malformed.
+  ASSERT(type.IsFinalized() && !type.IsMalformed() && !type.IsMalbounded());
   ValueGraphVisitor for_value(owner(), temp_index());
   node->left()->Visit(&for_value);
   Append(for_value);
   const String& dst_name = String::ZoneHandle(
       Symbols::New(Exceptions::kCastErrorDstName));
-  if (type.IsMalformed() || type.IsMalbounded()) {
-    ReturnValue(BuildAssignableValue(node->token_pos(),
-                                     for_value.value(),
-                                     type,
-                                     dst_name));
+  if (CanSkipTypeCheck(node->token_pos(),
+                       for_value.value(),
+                       type,
+                       dst_name)) {
+    ReturnValue(for_value.value());
+    return;
+  }
+  PushArgumentInstr* push_left = PushArgument(for_value.value());
+  PushArgumentInstr* push_instantiator = NULL;
+  PushArgumentInstr* push_type_args = NULL;
+  if (type.IsInstantiated()) {
+    push_instantiator = PushArgument(BuildNullValue());
+    push_type_args = PushArgument(BuildNullValue());
   } else {
-    if (CanSkipTypeCheck(node->token_pos(),
-                         for_value.value(),
-                         type,
-                         dst_name)) {
-      ReturnValue(for_value.value());
-      return;
-    }
-    PushArgumentInstr* push_left = PushArgument(for_value.value());
-    PushArgumentInstr* push_instantiator = NULL;
-    PushArgumentInstr* push_type_args = NULL;
-    if (type.IsInstantiated()) {
-      push_instantiator = PushArgument(BuildNullValue());
-      push_type_args = PushArgument(BuildNullValue());
-    } else {
-      BuildTypecheckPushArguments(node->token_pos(),
-                                  &push_instantiator,
-                                  &push_type_args);
-    }
-    ZoneGrowableArray<PushArgumentInstr*>* arguments =
-        new ZoneGrowableArray<PushArgumentInstr*>(4);
-    arguments->Add(push_left);
-    arguments->Add(push_instantiator);
-    arguments->Add(push_type_args);
-    Value* type_arg = Bind(new ConstantInstr(type));
-    arguments->Add(PushArgument(type_arg));
-    const intptr_t kNumArgsChecked = 1;
-    InstanceCallInstr* call = new InstanceCallInstr(
-        node->token_pos(),
-        Library::PrivateCoreLibName(Symbols::_as()),
-        node->kind(),
-        arguments,
-        Object::null_array(),  // No argument names.
-        kNumArgsChecked,
-        owner()->ic_data_array());
-    ReturnDefinition(call);
+    BuildTypecheckPushArguments(node->token_pos(),
+                                &push_instantiator,
+                                &push_type_args);
   }
+  ZoneGrowableArray<PushArgumentInstr*>* arguments =
+      new ZoneGrowableArray<PushArgumentInstr*>(4);
+  arguments->Add(push_left);
+  arguments->Add(push_instantiator);
+  arguments->Add(push_type_args);
+  Value* type_arg = Bind(new ConstantInstr(type));
+  arguments->Add(PushArgument(type_arg));
+  const intptr_t kNumArgsChecked = 1;
+  InstanceCallInstr* call = new InstanceCallInstr(
+      node->token_pos(),
+      Library::PrivateCoreLibName(Symbols::_as()),
+      node->kind(),
+      arguments,
+      Object::null_array(),  // No argument names.
+      kNumArgsChecked,
+      owner()->ic_data_array());
+  ReturnDefinition(call);
 }