[compiler-rt] [asan] Detect dereferencing zero-alloc as heap buffer overflow (PR #155943)

[Thurston Dang via llvm-commits]

thurstond wrote:

> Windows is broken https://lab.llvm.org/staging/#/builders/37

Same issue; fix hasn't landed. Windows bots are surprisingly slow.
e.g., the most recently finished bot run (https://lab.llvm.org/staging/#/builders/37/builds/713) is building off:
```
Date	August 29, 2025 11:24 AM (8 hours ago)
Revision	0499eb83fa92001d7f72623e2954bf2c340e0f79
```


https://github.com/llvm/llvm-project/pull/155943