HEIMDAL_MUTEX_destroy
#define HEIMDAL_MUTEX_destroy(m) do {if ((*(m)) != 0) abort(); } while(0)
#define HEIMDAL_MUTEX_destroy(m) do { (void)(m); } while(0)
#define HEIMDAL_MUTEX_destroy(m) mutex_destroy(m)
#define HEIMDAL_MUTEX_destroy(m) pthread_mutex_destroy(m)