update

os/mutex.cpp

@@ -47,7 +47,6 @@ void zmutex::unlock() {
  *                                 zlock_guard                                 *
  *******************************************************************************/
 zlock_guard::zlock_guard(zmutex& mutex) : m_mutex(mutex) {
-  m_mutex = mutex;
   m_mutex.lock();
 }
 zlock_guard::~zlock_guard() { m_mutex.unlock(); }