rmaprath added a comment. In https://reviews.llvm.org/D28229#634278, @compnerd wrote:
> I dont think that making Win32 threading an external one makes much sense > unless we also do the same for pthreads. Its just as valid a threading model > as pthreads, so why give preferential treatment to that? (Sure, there are > more buildbots using it, but thats not a strong technical justification). If the Win32 threading is support is going to be upstreamed, yes, it makes sense to give it the same treatment as pthreads (keep it inside `__threading_support`). libcxx has been tied to pthreads for a while, would be good to see something else supported as well. This will also allow us to iron out pthread-isms from the sources into the threading API. I have a couple of patches in that area (which I discovered while implementing the libcxx threading API with a different thread implementation), will put them up for review soon. ================ Comment at: include/__threading_support:30-50 #if defined(_LIBCPP_HAS_THREAD_API_EXTERNAL) && \ + !__libcpp_has_include(<__external_threading>) +// If the <__external_threading> header is absent, build libc++ against a +// pthread-oriented thread api but leave out its implementation. This setup +// allows building+testing of an externally-threaded library variant (on any +// platform that supports pthreads). Here, an 'externally-threaded' library +// variant is one where the implementation of the libc++ thread api is provided ---------------- compnerd wrote: > Can you break this down into this which IMO is far more readable: > > #if defined(_LIBCPP_HAS_THREAD_API_EXTERNAL) > #if __libcpp_has_include(<external_threading>) > #include <__external_threading> > #else > // Why pthread? > #define _LIBCPP_HAS_THREAD_API_EXTERNAL_PTHREAD > #endif > #endif > > #if defined(_LIBCPP_HAS_THREAD_API_PTHREAD) || > defined(_LIBCPP_HAS_THREAD_API_EXTERNAL_PTHREAD) > #include <pthread.h> > #include <sched.h> > #endif The reason I kept it in the current form is, when `__external_threading` is present, everything else in this header needs to be silenced. This is enforced by the current form because everything else in this header lives inside the `#else` side of the `__external_threading` inclusion. Sure, the header will be a bit more readable if we arrange it the way you suggested, but then it's easy to add something to the header in a way that does not get removed when `__external_threading` is present. https://reviews.llvm.org/D28229 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
