I believe this thread_local support is in XCode 8.2. From the link you shared:
> Xcode 8.2 requires a Mac running macOS 10.11.5 or later This means that users can upgrade the compiler on El Capitan just fine without a system upgrade. Users on Yosemite need to do a system upgrade to pick up the new compiler however. On Mon, Dec 19, 2016 at 12:33 PM, Joris Van Remoortere <jo...@mesosphere.io> wrote: > Is my understanding incorrect regarding the ability to upgrade the compiler > version on Yosemite and El Capitan without requiring a full system upgrade? > > @Mpark are you making a case for not updating to `thread_local` just yet? > > — > *Joris Van Remoortere* > Mesosphere > > On Fri, Dec 16, 2016 at 11:11 AM, Michael Park <mp...@apache.org> wrote: > > > Brief survey from the #dev channel: https://mesos.slack.com/ > > archives/dev/p1481760285000430 > > > > Yosemite 10.10: Fail. Compilation error. (by @hausdorff > > https://mesos.slack.com/archives/dev/p1481760552000435) > > El Capitan 10.11: Fail. Compilation error. (by @zhitao > > https://mesos.slack.com/files/zhitao/F3F7WUCNM/-.diff) > > Sierra 10.12: Success (by @mpark) > > > > On Wed, Dec 14, 2016 at 3:27 PM, Joris Van Remoortere < > jo...@mesosphere.io > > > > > wrote: > > > > > The time has come and we finally have `thread_local` support in the > Apple > > > tool chain: > > > https://developer.apple.com/library/content/releasenotes/Dev > > > eloperTools/RN-Xcode/Introduction.html > > > > > > In our code base we have a special exception for Apple that defines our > > > thread local to be `__thread` rather than the c++11 standard > > > `thread_local`. > > > https://github.com/apache/mesos/blob/812e5e3d4e4d9e044a1cfe6 > > > cc7eaab10efb499b6/3rdparty/stout/include/stout/thread_local.hpp > > > > > > A consequence of using `__thread` on Apple is that initializers for > > thread > > > locals are required to be constant expressions. This is not the case > for > > > the c++11 standard `thread_local`. > > > > > > I would like to propose that we remove this exception on the Apple > > platform > > > now that the Apple toolchain supports the c++11 standard. > > > > > > As I am not a common user of the Apple development experience I would > > like > > > to ask for some input from the community as to whether requiring this > > > toolchain update is acceptable, and if we need a deprecation period or > if > > > we can just make this change now. > > > > > > I am leaning towards no deprecation period as I am not aware of > > production > > > environments running on systems that define `__APPLE__`. > > > — > > > *Joris Van Remoortere* > > > Mesosphere > > > > > > > -- > Zameer Manji >
