_thr_attr_setguardsize
__weak_reference(_thr_attr_setguardsize, pthread_attr_setguardsize);
__weak_reference(_thr_attr_setguardsize, _pthread_attr_setguardsize);
[PJT_ATTR_SETGUARDSIZE] = {DUAL_ENTRY(_thr_attr_setguardsize)},
int _thr_attr_setguardsize(pthread_attr_t *, size_t);