[libcxx-commits] [PATCH] D65348: enable <atomic> header on systems without thread-support

[Louis Dionne via Phabricator via libcxx-commits]

ldionne added a reviewer: ldionne.
ldionne added a comment.
Herald added a subscriber: dexonsmith.

This change makes sense to me as-is. I agree with @__simt__ that we want people to use `-ffreestanding` in the future, however I'm also with @burnpanck on the fact that Freestanding is currently ill-defined (both in the Standard and in existing practice -- nobody seems to have agreement on what exactly is in there).

Since we currently allow disabling the use of threads without using `-ffreestanding`, I think it makes sense to _not_ require `-ffreestanding` to enable the builtin-only atomics. Once we figure out what exactly is in `freestanding`, we can change that and guard all those features by `#if defined(_LIBCPP_FREESTANDING) && <existing feature>` (or something along those lines), with the goal of requiring the use of `-ffreestanding` to enable those features. @__simt__ Would you still rather requiring the use of `-ffreestanding` to enable builtin-only atomics?


Repository:
  rCXX libc++

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D65348/new/

https://reviews.llvm.org/D65348