title: c++11 thread_local keyword support in visual studio 11
body: <p>So there's a <a href="http://blogs.msdn.com/b/vcblog/archive/2011/09/12/10209291.aspx" rel="nofollow noreferrer">list of c++11 features supported by visual studio</a>.</p>
  
  <p>thread_local support is marked as partial. I was unable to find an explanation of what exactly partial support means here. Did they just alias __declspec(thread)?</p>
  
  <p>I could just use boost::thread_specific_ptr, but there seem to be some reports that <a href="https://stackoverflow.com/questions/5398987/is-it-expected-that-use-of-boostthread-specific-ptrget-be-slow-any-work">boost::thread_specific_ptr is slow</a>. That may or may not be true.</p>
  
  <p>Specifically I want fast TLS on x86/x64 on the most recent linux+gcc and windows+msvc. Fast meaning no system calls where possible (I think this is possible for the platforms above.)</p>