On Wed, Aug 10, 2011 at 8:11 PM, Jean-Sebastien Delfino <jsdelf...@apache.org> wrote: > On Wed, Aug 10, 2011 at 6:45 AM, dsh <daniel.hais...@googlemail.com> wrote: >> Hi Jean-Sebastien, >> >> On Wed, Aug 10, 2011 at 6:45 AM, Jean-Sebastien Delfino >> <jsdelf...@apache.org> wrote: >>> >>> That's what I meant when I mentioned 'convert usages of __thread to >>> Posix thread TLS calls' in my previous post [1]. >>> >>> __thread works for me with GCC on Mac OS X (using the GCC build from >>> the HPC project [2]), but causes a compile error with Clang/LLVM. It's >>> listed as a limitation of Clang on Mac OS X in the Clang user manual >>> (look for __thread on this page [3]). >>> >> >> Does "Works for me" mean it compiles for you just fine AND during >> runtime you are getting the expected behavior or does it just mean the >> code compiles just fine if using GCC? >> >> I am asking cause I googled a bit last night and from what I found I >> had the feeling thread local isn't really supported on OS X during >> runtime. >> > > Hi Daniel! > > __thread compiles and behaves as expected for me on OS X with GCC 4.6 > (the version referenced in the macos/macos-install script). > > I've added some test logic to kernel/parallel-test.cpp to help verify > that (see SVN r1156460). > > Parallel-test built with GCC works, showing that __thread is correctly > implemented by GCC on OS X. > > After commenting __thread on parallel-test.cpp:line 134, parallel-test > breaks with an assertion error, showing that the test is actually > effective at testing thread local storage. > > I'm hoping that this additional test code will help you when you > implement thread local storage over the pthread API. In the meantime > you don't have to worry about it if you --disable-threads :) >
Hi Daniel, In SVN revision 1162472 I've replaced the references to __thread by a new portable implementation of thread local storage using the POSIX pthread key_create, key_delete, setspecific and getspecific functions. See the perthread_ptr class in kernel/parallel.hpp, the tests in kernel/parallel-test.cpp and other usages throughout the code base. Compared to __thread, it also works on class and struct fields and can take an initialization function responsible for creating the thread specific value. Hope that helps... We shouldn't need to use --disable-threads anymore with CLang/LLVM. -- Jean-Sebastien
