[compiler-rt] Work around a C language bug in libFuzzer (PR #96775)

[Fangrui Song via llvm-commits]

https://github.com/MaskRay approved this pull request.

The subject line can be named `[fuzzer] xxx` or `[Fuzzer] xxx`.

"work around a C language bug" is not a good way to phrase this usability issue. It's unfortunate and should be fixed, but I am not sure calling it a language bug is useful.

https://github.com/llvm/llvm-project/pull/96775