Fix for GCMole issue.

src/runtime.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 11259 matching lines @@
   }
   if (i < scope_info->LocalCount()) {
     // Get the context containing declarations.
     Handle<Context> context(
         Context::cast(it.frame()->context())->declaration_context());
     for (; i < scope_info->LocalCount(); ++i) {
       Handle<String> name(scope_info->LocalName(i));
       VariableMode mode;
       InitializationFlag init_flag;
       locals->set(i * 2, *name);
-      locals->set(i * 2 + 1, context->get(
-          scope_info->ContextSlotIndex(*name, &mode, &init_flag)));
+      int context_slot_index =
+          scope_info->ContextSlotIndex(*name, &mode, &init_flag);
+      Object* value = context->get(context_slot_index);
+      locals->set(i * 2 + 1, value);
     }
   }
 
   // Check whether this frame is positioned at return. If not top
   // frame or if the frame is optimized it cannot be at a return.
   bool at_return = false;
   if (!is_optimized && index == 0) {
     at_return = isolate->debug()->IsBreakAtReturn(it.frame());
   }
 
@@ skipping 3816 matching lines @@
     // Handle last resort GC and make sure to allow future allocations
     // to grow the heap without causing GCs (if possible).
     isolate->counters()->gc_last_resort_from_js()->Increment();
     isolate->heap()->CollectAllGarbage(Heap::kNoGCFlags,
                                        "Runtime::PerformGC");
   }
 }
 
 
 } }  // namespace v8::internal