id summary reporter owner description type status milestone component version severity resolution keywords cc 5194 unique_lock::unlock() does not protect modification of is_locked with mutex Andrei Kazarov "Shouldn't first is_locked=false and then m->unlock()? Otherwise is_locked value is undetermined in case of simultaneous calls to lock() and unlock()... void unlock() { ... m->unlock(); is_locked=false; } void lock() { ... m->lock(); is_locked=true; } " Bugs closed To Be Determined thread Boost 1.45.0 Problem invalid