Boost 1.37.0, Red Hat Enterprise Linux 5 x86_64, gcc 4.1: The following simple test establishes a barrier with thread count 2. One of the threads destroys the barrier after returning from wait(). This results in sporadic assertions from ~mutex(). boost/thread/pthread/mutex.hpp:45: boost::mutex::~mutex(): Assertion `!pthread_mutex_destroy(&m)' failed. #1 0x00000038306295d6 in __assert_fail () from /lib64/libc.so.6 #2 0x000000000040245a in ~mutex (this=0x1f63f010) at boost/thread/pthread/mutex.hpp:45 #3 0x0000000000402488 in ~barrier (this=0x1f63f010) at boost/thread/barrier.hpp:24 I assume that this usage of barrier is not supported/allowed. One cannot assume that the barrier can be destroyed just because the corresponding thread returned from wait(). Is this conclusion correct? Regards, Peter. #include <boost/scoped_ptr.hpp> #include <boost/thread/barrier.hpp> #include <boost/thread/thread.hpp> boost::scoped_ptr<boost::barrier> barrier; void f() { barrier->wait(); } int main(void) { barrier.reset(new boost::barrier(2)); boost::thread thread(boost::bind(&f)); barrier->wait(); barrier.reset(); thread.join(); return 0; }