[libcxx-commits] [libcxx] Remove incorrect forward-declaration of lgamma_r header (PR #80979)

[Yuriy Chernyshov via libcxx-commits]

georgthegreat wrote:

We have this patch ported locally and it works just fine (though our CI tests against `macos-version-min=11.0`).
Maybe this specific CI turns `_REENTRANT` off somehow.

There is no cuda compiler under MacOS, so we may simply forward-declare it under `__APPLE__`

https://github.com/llvm/llvm-project/pull/80979