THR_PAGE_SIZE_MIN
_Static_assert(sizeof(struct pthread_barrier) <= THR_PAGE_SIZE_MIN,
_Static_assert(sizeof(struct pthread_cond) <= THR_PAGE_SIZE_MIN,
_Static_assert(sizeof(struct pthread_mutex) <= THR_PAGE_SIZE_MIN,
THR_ASSERT(page_size >= THR_PAGE_SIZE_MIN,
_Static_assert(sizeof(struct pthread_spinlock) <= THR_PAGE_SIZE_MIN,
_Static_assert(sizeof(struct pthread_rwlock) <= THR_PAGE_SIZE_MIN,