[PATCH] D137917: [cmake] Fix _GNU_SOURCE being added unconditionally

[Trass3r via Phabricator via llvm-commits]

Trass3r added a comment.

I only came across it when testing a PCH build.
https://github.com/Trass3r/llvm-project/actions/runs/3423679621/jobs/5702548183

  Warning: <built-in>(1,9): warning: definition of macro '_GNU_SOURCE' does not match definition in precompiled header [-Wclang-cl-pch]

It was set for clang but not for llvm when building with clang-cl.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D137917/new/

https://reviews.llvm.org/D137917