gcc/testsuite/gcc.c-torture/execute/20010910-1.c

   1 /* Test case contributed by Ingo Rohloff <rohloff@in.tum.de>.
   2    Code distilled from Linux kernel.  */
   3
   4 /* Compile this program with a gcc-2.95.2 using
   5    "gcc -O2" and run it. The result will be that
   6    rx_ring[1].next == 0   (it should be == 14)
   7    and
   8    ep.skbuff[4] == 5      (it should be 0)
   9 */
  10
  11 extern void abort(void);
  12
  13 struct epic_rx_desc
  14 {
  15   unsigned int next;
  16 };
  17
  18 struct epic_private
  19 {
  20   struct epic_rx_desc *rx_ring;
  21   unsigned int rx_skbuff[5];
  22 };
  23
  24 static void epic_init_ring(struct epic_private *ep)
  25 {
  26   int i;
  27
  28   for (i = 0; i < 5; i++)
  29   {
  30     ep->rx_ring[i].next = 10 + (i+1)*2;
  31     ep->rx_skbuff[i] = 0;
  32   }
  33   ep->rx_ring[i-1].next = 10;
  34 }
  35
  36 static int check_rx_ring[5] = { 12,14,16,18,10 };
  37
  38 int main(void)
  39 {
  40   struct epic_private ep;
  41   struct epic_rx_desc rx_ring[5];
  42   int i;
  43
  44   for (i=0;i<5;i++)
  45   {
  46     rx_ring[i].next=0;
  47     ep.rx_skbuff[i]=5;
  48   }
  49
  50   ep.rx_ring=rx_ring;
  51   epic_init_ring(&ep);
  52
  53   for (i=0;i<5;i++)
  54   {
  55     if ( rx_ring[i].next != check_rx_ring[i] ) abort();
  56     if ( ep.rx_skbuff[i] != 0 ) abort();
  57   }
  58   return 0;
  59 }