mtx_recursive
case mtx_plain | mtx_recursive:
case mtx_timed | mtx_recursive:
VERIFY3S(mtx_init(&mtx, mtx_plain | mtx_recursive), ==, thrd_success);
VERIFY3S(mtx_init(&mtx, mtx_timed | mtx_recursive), ==, thrd_success);
VERIFY3S(mtx_init(&mtx, mtx_plain | mtx_recursive), ==, thrd_success);