[PATCH] D28220: provide Win32 native threading

[Eric Fiselier via Phabricator via cfe-commits]

EricWF requested changes to this revision.
EricWF added a comment.
This revision now requires changes to proceed.

This needs to be rebased following the `<__threading_support>` cleanup in r291275.


Repository:
  rL LLVM

https://reviews.llvm.org/D28220