As shown in this answer, clang from Xcode on Mac OSX does not support thread_local
storage even with C++11 flags set. Even on the latest version, Apple LLVM version 7.0.0 (clang-700.1.76), Target: x86_64-apple-darwin15.0.0, Thread model: posix, does not support thread_local
:
../../src/dir/sysArch.h:1505:3: error: thread-local storage is not supported
for the current target
thread_local
^