[clang] e6629be - [AIX] Define __STDC_NO_ATOMICS__ and __STDC_NO_THREADS__ predefined macros

[Joerg Sonnenberger via cfe-commits]

On Mon, Jun 07, 2021 at 07:04:36PM -0700, via cfe-commits wrote:
> 
> Author: =Jake Egan
> Date: 2021-06-07T22:04:18-04:00
> New Revision: e6629be31e67190f0a524f009752d73410894560
> 
> URL: https://github.com/llvm/llvm-project/commit/e6629be31e67190f0a524f009752d73410894560
> DIFF: https://github.com/llvm/llvm-project/commit/e6629be31e67190f0a524f009752d73410894560.diff
> 
> LOG: [AIX] Define __STDC_NO_ATOMICS__ and __STDC_NO_THREADS__ predefined macros

I find the justification for this a bit strange. Neither one has to be
implemented in libc. compiler-rt implements the former with the mixing
caveats applied and there are portable implementations of the latter
based on pthread. I would expect them to work well enough on AIX, too.
So this seems to do more harm than good?

Joerg