Check that after a weak callback, the handle is either dead or strong

src/global-handles.cc

 // Copyright 2009 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 253 matching lines @@
       HandleScope handle_scope(isolate);
       Handle<Object> handle(*object, isolate);
       v8::WeakCallbackData<v8::Value, void> data(
           reinterpret_cast<v8::Isolate*>(isolate),
           v8::Utils::ToLocal(handle),
           par);
       weak_callback_(data);
     }
     // Absence of explicit cleanup or revival of weak handle
     // in most of the cases would lead to memory leak.
-    ASSERT(state() != NEAR_DEATH);
+    CHECK(state() != NEAR_DEATH);
     return true;
   }
 
   inline GlobalHandles* GetGlobalHandles();
 
  private:
   inline NodeBlock* FindBlock();
   inline void IncreaseBlockUses();
   inline void DecreaseBlockUses();
 
@@ skipping 799 matching lines @@
   ASSERT_EQ(isolate->heap()->the_hole_value(), blocks_[block][offset]);
   blocks_[block][offset] = object;
   if (isolate->heap()->InNewSpace(object)) {
     new_space_indices_.Add(size_);
   }
   *index = size_++;
 }
 
 
 } }  // namespace v8::internal