thrd_equal
extern int thrd_equal(thrd_t, thrd_t);
VERIFY3S(thrd_equal(self, self), !=, 0);
VERIFY3S(thrd_equal(self, other), ==, 0);
VERIFY3S(thrd_equal(other, other), !=, 0);
VERIFY3S(thrd_equal(self, self), !=, 0);