[libcxx-commits] [libcxx] [libc++] Revert "Do not redeclare lgamma_r when targeting the LLVM C library (#102036) (PR #125587)

[Nikolas Klauser via libcxx-commits]

philnik777 wrote:

Would it make sense to partially revert? IIUC this still works when targeting linux with the LLVM libc, so we could just revert the inclusion of `<features.h>` if available.

https://github.com/llvm/llvm-project/pull/125587