gcc/testsuite/gcc.dg/pr62030.c

   1 /* { dg-do run } */
   2 /* { dg-options "-O2" } */
   3
   4 extern void abort (void);
   5
   6 struct node
   7 {
   8   struct node *next;
   9   struct node *prev;
  10 };
  11
  12 struct node node;
  13
  14 struct head
  15 {
  16   struct node *first;
  17 };
  18
  19 struct head heads[5];
  20
  21 int k = 2;
  22
  23 struct head *head = &heads[2];
  24
  25 static int __attribute__((noinline))
  26 foo (void)
  27 {
  28   node.prev = (void *)head;
  29   head->first = &node;
  30
  31   struct node *n = head->first;
  32   struct head *h = &heads[k];
  33   struct node *next = n->next;
  34
  35   if (n->prev == (void *)h)
  36     h->first = next;
  37   else
  38     n->prev->next = next;
  39
  40   n->next = h->first;
  41   return n->next == &node;
  42 }
  43
  44 int
  45 main (void)
  46 {
  47   if (foo ())
  48     abort ();
  49   return 0;
  50 }