[libc-commits] [libc] [libc] Remove obsolete LIBC_HAS_BUILTIN macro (PR #86554)

[Nick Desaulniers via libc-commits]

nickdesaulniers wrote:

> Okay I vaguely recall one niche use-case that this will break. Currently I build the RPC loader / server utilities in the main LLVM build similar to how we build `libc-hdrgen`. The minimum GCC compiler right now is 7.4 which doesn't support this https://godbolt.org/z/zaTvbz1os. These utilities include a handful of files, which I believe use `LIBC_HAS_BUILTIN` (like atomic.h). If someone were to build LLVM with an older GCC this would no longer work and it would error out.

Ah, thanks for the note.  I'm curious, when you build the RPC loader / server utilities, what version of GCC are you using?

https://github.com/llvm/llvm-project/pull/86554