[PATCH] D28229: [libcxx] Fix testing of the externally-threaded library build after r290850

[Asiri Rathnayake via Phabricator via cfe-commits]

rmaprath added a comment.

I will commit this now to get the testing working again. Thought of putting up the patch for review in case if there is a better way to do this.

@compnerd: I wondered, for windows threading support, why not do something similar to `__external_threading` (and how it is handled in `__threading_support`) and offload the entire implementation to a separate windows-only header?


https://reviews.llvm.org/D28229