1 extern void abort (void);
2 
3 struct delay_block {
4   struct delay_block *succ;
5 };
6 
7 static struct delay_block Timer_Queue;
8 
time_enqueue(struct delay_block * d)9 struct delay_block* time_enqueue (struct delay_block *d)
10 {
11   struct delay_block *q = Timer_Queue.succ;
12   d->succ =  (void *)0;
13   return Timer_Queue.succ;
14 }
15 
main(void)16 int main(void)
17 {
18   Timer_Queue.succ = &Timer_Queue;
19   if (time_enqueue (&Timer_Queue) != (void*)0)
20     abort ();
21   return 0;
22 }
23 
24