_Tthr_rwlock_rdlock
[PJT_RWLOCK_RDLOCK] = {DUAL_ENTRY(_Tthr_rwlock_rdlock)},
int _Tthr_rwlock_rdlock(pthread_rwlock_t *);
__weak_reference(_Tthr_rwlock_rdlock, pthread_rwlock_rdlock);
__weak_reference(_Tthr_rwlock_rdlock, _pthread_rwlock_rdlock);