[embedded] Fix a memory leak caused by incorrect refcounting logic around doNotFreeBit #77121
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…ound doNotFreeBit
kubamracek
requested review from
MaxDesiatov,
phausler,
mikeash,
al45tair,
rauhul,
zoecarver and
eeckstein
|
@swift-ci please test |
rauhul
approved these changes
Oct 20, 2024
al45tair
approved these changes
Oct 21, 2024
|
I'm not quite following how this works, can you explain a bit? It doesn't look like |
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Looks like we had a major memory leak caused by the changes from #76231. We can't set the refcount to
HeapObject.immortalRefCount(0xffff_ffff) because that (accidentally) also includesHeapObject.doNotFreeBit(0x8000_000). Let's separate the two -- immortalRefCount is now only 0x7fff_ffff and the highest bit is used as a doNotFreeBit regardless of whether the refcount is immortal or not.Fixes #76998