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

[Louis Dionne via libcxx-commits]

https://github.com/ldionne commented:

This basically LGTM with a few comments. Let's try to land this soon to avoid many merge conflicts. I'd still like to have another look once the comments have been addressed.

This simplifies some complicated conditionals *so much*.

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