[libcxx-commits] [libcxx] [libcxxabi] [libc++][RFC] Always define internal feature test macros (PR #89178)

[Louis Dionne via libcxx-commits]

ldionne wrote:

In light of the discussion we had in the libc++ monthly, I think we could update this patch. @philnik777 

https://github.com/llvm/llvm-project/pull/89178