kHasWeakRef        96 MMgc/GCAlloc.h enum ItemBit { kMark=1, kQueued=2, kFinalize=4, kHasWeakRef=8, kFreelist=kMark|kQueued };
kHasWeakRef        56 MMgc/GCLargeAlloc.h kHasWeakRef       = 0x8,