[Boost-users] boost::thread and helgrind

I am currently fooling around with boost::thread. After writing a short example program (featuring boost::thread and boost::interprocess::interprocess_semaphore), I ran helgrind against it and got some "Possible data race" errors. The program does nothing but start two threads and serialize them via the semaphore and I am unsure whether a) I did some error I am not aware of b) helgrind reports false positives I would be glad if someone could look at my code (attached) and give me a hint. Frederick Roth PS: Software versions are boost-1.47.0, valgrind-3.6.1, gcc 4.6.2, c++0x