Remove unused-but-set variable from objects.cc.

src/objects.cc

 // Copyright 2012 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 7544 matching lines @@
   if (code->kind() != Code::FUNCTION) return true;
   return code->optimizable();
 }
 
 
 MaybeObject* JSObject::OptimizeAsPrototype() {
   if (IsGlobalObject()) return this;
 
   // Make sure prototypes are fast objects and their maps have the bit set
   // so they remain fast.
-  Map* proto_map = map();
   if (!HasFastProperties()) {
     MaybeObject* new_proto = TransformToFastProperties(0);
     if (new_proto->IsFailure()) return new_proto;
     ASSERT(new_proto == this);
-    proto_map = map();
   }
   return this;
 }
 
 
 MaybeObject* JSFunction::SetInstancePrototype(Object* value) {
   ASSERT(value->IsJSReceiver());
   Heap* heap = GetHeap();
 
   // First some logic for the map of the prototype to make sure it is in fast
@@ skipping 5669 matching lines @@
   set_year(Smi::FromInt(year), SKIP_WRITE_BARRIER);
   set_month(Smi::FromInt(month), SKIP_WRITE_BARRIER);
   set_day(Smi::FromInt(day), SKIP_WRITE_BARRIER);
   set_weekday(Smi::FromInt(weekday), SKIP_WRITE_BARRIER);
   set_hour(Smi::FromInt(hour), SKIP_WRITE_BARRIER);
   set_min(Smi::FromInt(min), SKIP_WRITE_BARRIER);
   set_sec(Smi::FromInt(sec), SKIP_WRITE_BARRIER);
 }
 
 } }  // namespace v8::internal