Fix ASSERT by reordering the initialization of the arguments boilerplate.

src/bootstrapper.cc

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 1066 matching lines @@
     ASSERT(result->map()->inobject_properties() > Heap::kArgumentsCalleeIndex);
     ASSERT(result->map()->inobject_properties() > Heap::kArgumentsLengthIndex);
 
     // Check the state of the object.
     ASSERT(result->HasFastProperties());
     ASSERT(result->HasFastElements());
 #endif
   }
 
   {  // --- aliased_arguments_boilerplate_
-    Handle<Map> old_map(global_context()->arguments_boilerplate()->map());
-    Handle<Map> new_map = factory->CopyMapDropTransitions(old_map);
-    new_map->set_pre_allocated_property_fields(2);
-    Handle<JSObject> result = factory->NewJSObjectFromMap(new_map);
-    new_map->set_elements_kind(NON_STRICT_ARGUMENTS_ELEMENTS);
     // Set up a well-formed parameter map to make assertions happy.
     Handle<FixedArray> elements = factory->NewFixedArray(2);
     elements->set_map(heap->non_strict_arguments_elements_map());
     Handle<FixedArray> array;
     array = factory->NewFixedArray(0);
     elements->set(0, *array);
     array = factory->NewFixedArray(0);
     elements->set(1, *array);
-    Handle<Map> non_strict_arguments_elements_map =
-        factory->GetElementsTransitionMap(result,
-                                          NON_STRICT_ARGUMENTS_ELEMENTS);
-    result->set_map(*non_strict_arguments_elements_map);
+
+    Handle<Map> old_map(global_context()->arguments_boilerplate()->map());
+    Handle<Map> new_map = factory->CopyMapDropTransitions(old_map);
+    new_map->set_pre_allocated_property_fields(2);
+    Handle<JSObject> result = factory->NewJSObjectFromMap(new_map);
+    // Set elements kind after allocating the object because
+    // NewJSObjectFromMap assumes a fast elements map.
+    new_map->set_elements_kind(NON_STRICT_ARGUMENTS_ELEMENTS);
+    result->set_elements(*elements);
     ASSERT(result->HasNonStrictArgumentsElements());
-    result->set_elements(*elements);
     global_context()->set_aliased_arguments_boilerplate(*result);
   }
 
   {  // --- strict mode arguments boilerplate
     const PropertyAttributes attributes =
       static_cast<PropertyAttributes>(DONT_ENUM | DONT_DELETE | READ_ONLY);
 
     // Create the ThrowTypeError functions.
     Handle<FixedArray> callee = factory->NewFixedArray(2, TENURED);
     Handle<FixedArray> caller = factory->NewFixedArray(2, TENURED);
@@ skipping 1150 matching lines @@
   return from + sizeof(NestingCounterType);
 }
 
 
 // Called when the top-level V8 mutex is destroyed.
 void Bootstrapper::FreeThreadResources() {
   ASSERT(!IsActive());
 }
 
 } }  // namespace v8::internal