tree f271c8ba8789030905c437a6cb2368f066db1c90
parent fc57bc380455487bfccbd9f561dd3f16ad8b120f
author Robert Sayre <sayrer@gmail.com> 1518965266 -0800
committer Paul Wankadia <junyer@google.com> 1518968062 +0000

Omit -pthread option on Darwin

The copy of Clang shipped with XCode 9.2 emits a warning when this
option is passed.

"clang: warning: argument unused during compilation:
'-pthread' [-Wunused-command-line-argument]"

This makes the build log very noisy, since the warning is emitted
for libre2 and every test.

Change-Id: I7714e08f66b51a86061016cae26f9b8b4f75ad9a
Reviewed-on: https://code-review.googlesource.com/23791
Reviewed-by: Paul Wankadia <junyer@google.com>