Make cells pointing to JSObjects weak in optimized code.

src/heap.cc

Index: src/heap.cc
diff --git a/src/heap.cc b/src/heap.cc
index f6c6ae6e3a68af10513a5fbc7c67957154dc021a..ebd72737709ab855d2266126eaacebab8c2643ef 100644
--- a/src/heap.cc
+++ b/src/heap.cc
@@ -3304,6 +3304,12 @@ bool Heap::CreateInitialObjects() {
   }
   set_natives_source_cache(FixedArray::cast(obj));
 
+  { MaybeObject* maybe_obj = AllocateCell(undefined_value());
+    if (!maybe_obj->ToObject(&obj)) return false;
+  }
+  set_undefined_cell(Cell::cast(obj));
+

[Michael Starzinger, 2014/01/10 13:45:19]

nit: Only one empty new-line here.

[ulan, 2014/01/13 11:35:06]

Done.

+
   // Allocate object to hold object observation state.
   { MaybeObject* maybe_obj = AllocateMap(JS_OBJECT_TYPE, JSObject::kHeaderSize);
     if (!maybe_obj->ToObject(&obj)) return false;