Mutex should be hold when calling
pthread_cond_signal().  This function should look like:


PyThread_release_lock(PyThread_type_lock lock)
{
        pthread_lock *thelock = (pthread_lock *)lock;
        int status, error = 0;

        dprintf(("PyThread_release_lock(%p) called\n",
lock));

        status = pthread_mutex_lock( &thelock->mut );
        CHECK_STATUS("pthread_mutex_lock[3]");

        thelock->locked = 0;
        /* ***** call pthread_cond_signal before unlock
mutex */
        status = pthread_cond_signal(
&thelock->lock_released );
        CHECK_STATUS("pthread_cond_signal");

        status = pthread_mutex_unlock( &thelock->mut );
        CHECK_STATUS("pthread_mutex_unlock[3]");

        /* wake up someone (anyone, if any) waiting on
the lock */
}