TEST(r, pthread_mutex_init(&mtx, &mtx_a), "initializing robust mutex");
TEST(r, pthread_mutex_lock(&mtx), "locking robust mutex");
TEST(r, pthread_mutex_unlock(&mtx), "unlocking robust mutex");
TEST(r, pthread_mutex_init(&mtx, &mtx_a), "initializing robust mutex");
TEST(r, pthread_mutex_lock(&mtx), "locking robust mutex");
TEST(r, pthread_mutex_unlock(&mtx), "unlocking robust mutex");