[compiler-rt] [win/asan] Improve SharedReAlloc with HEAP_REALLOC_IN_PLACE_ONLY. (PR #132558)

[Thurston Dang via llvm-commits]

https://github.com/thurstond commented:

My earlier comment stands:

  _"I still wonder whether implementing this will reduce bug detection. For example, some code might incorrectly not expect NULL to be returned (even though the allocator is allowed to do so), or perhaps returning NULL will force the user code to call realloc without HEAP_REALLOC_IN_PLACE_ONLY (thereby allowing stronger use-after-free detection)."_

Would you consider placing the new behavior configurable via an ASAN_OPTION?

https://github.com/llvm/llvm-project/pull/132558