[libc++] Work around gcc/Power9 bug in `include/thread`
authorJoel E. Denny <jdenny.ornl@gmail.com>
Wed, 10 Jun 2020 16:40:43 +0000 (12:40 -0400)
committerJoel E. Denny <jdenny.ornl@gmail.com>
Wed, 10 Jun 2020 16:40:43 +0000 (12:40 -0400)
commitd9a42ec98adcb1ebc0c3837715df4e5a50c7ccc0
tree7bb1e71c4b8355c891b02faf17caa584dcac8ff9
parent4b1b09fcc0d75ad4d5559f0b86049627174db585
[libc++] Work around gcc/Power9 bug in `include/thread`

This fixes PR39696, which breaks the libcxx build with gcc (I tested
7.5.0) on Power9.  This fix was suggested at

https://bugs.llvm.org/show_bug.cgi?id=39696#c38

but never applied.  It just reverts 0583d9ea8d5e, which reverses
components of the original fix in 3bf63cf3b366, which is correct.

Fixes https://llvm.org/PR39696

Reviewed By: ldionne

Differential Revision: https://reviews.llvm.org/D81438
libcxx/include/thread