folly/portability: add clang version check
authorIgor Sugak <sugak@fb.com>
Sun, 8 Nov 2015 08:32:52 +0000 (00:32 -0800)
committerfacebook-github-bot-1 <folly-bot@fb.com>
Sun, 8 Nov 2015 09:20:23 +0000 (01:20 -0800)
commit408597e5bc528477608785709ba3fa67ef64823f
treec33a3cd4d5767f44653971b0d5192648d91c71ba
parentcb65a6b273ae8c050333600816557755d488b63c
folly/portability: add clang version check

Summary: Define `__CLANG_PREREQ` macro to check version of clang.

Reviewed By: yfeldblum

Differential Revision: D2630325

fb-gh-sync-id: 3d666e554e8ddfc2c1fecd439aaf93f015829025
folly/Portability.h