| Index: src/runtime.cc | 
| diff --git a/src/runtime.cc b/src/runtime.cc | 
| index eba17a19437b86de7c502faf8f1f3d99cf2ba8f8..ba1389318c9428316d0dc033a83b6410f4cfad13 100644 | 
| --- a/src/runtime.cc | 
| +++ b/src/runtime.cc | 
| @@ -14515,8 +14515,8 @@ RUNTIME_FUNCTION(Runtime_LoadMutableDouble) { | 
| object->properties()->length()); | 
| } | 
| Handle<Object> raw_value(object->RawFastPropertyAt(field_index), isolate); | 
| -  RUNTIME_ASSERT(raw_value->IsNumber() || raw_value->IsUninitialized()); | 
| -  return *Object::NewStorageFor(isolate, raw_value, Representation::Double()); | 
| +  RUNTIME_ASSERT(raw_value->IsMutableHeapNumber()); | 
| +  return *Object::WrapForRead(isolate, raw_value, Representation::Double()); | 
| } | 
|  | 
|  | 
|  |