> I get a report about a race from helgrind, while everything looks well > synchronized to me. > Am I wrong?
> fprintf(stderr, "COND: %d\n", COND); > pthread_join(threadid, NULL); The problem is here. By the time you get here, Helgrind knows that COND has been accessed by both parent and child threads, and MU is used to protect it. But now you are using it without a lock. Helgrind cannot know that the child thread (run_pm) does not access COND again after the pthread_cond_signal (how could it know this without doing static analysis of the child's code?) If you change the order of these two lines, to > pthread_join(threadid, NULL); > fprintf(stderr, "COND: %d\n", COND); then it stops complaining. Because now the pthread_join tells Helgrind that the child can no longer access COND. That means, after the pthread_join, the parent is the only thread able to access COND, so it is OK for it to access COND without a lock. J ------------------------------------------------------------------------- SF.Net email is sponsored by: The Future of Linux Business White Paper from Novell. From the desktop to the data center, Linux is going mainstream. Let it simplify your IT future. http://altfarm.mediaplex.com/ad/ck/8857-50307-18918-4 _______________________________________________ Valgrind-developers mailing list Valgrind-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/valgrind-developers
