void
memory_barrier (void)
{
    __sync_synchronize();
}
int
atomic_add (int *i)
{
    return __sync_fetch_and_add (i, 1);
}
int
mutex_trylock (int *m)
{
    return __sync_lock_test_and_set (m, 1);
}
void
mutex_unlock (int *m)
{
    __sync_lock_release (m);
}

int
main (void)
{
    return 0;
}