gcc/testsuite/gcc.dg/uninit-pr89230-2.c

   1 /* PR middle-end/89230 - Bogus uninited usage warning with printf
   2    { dg-do compile }
   3    { dg-options "-O2 -Wall" } */
   4
   5 typedef __SIZE_TYPE__ size_t;
   6
   7 extern void* memset (void*, int, size_t);
   8 extern int printf (const char*, ...);
   9 extern int rand (void);
  10
  11 struct S
  12 {
  13   int a;
  14   int b;
  15 };
  16
  17 struct H
  18 {
  19   int c;
  20   int d;
  21 };
  22
  23 void getblk (void* blk)
  24 {
  25   struct S* s = (struct S*) blk;
  26   memset (blk, 0, 512);
  27   s->a = rand () & 1;
  28 }
  29
  30 struct H* gethdr (void* blk)
  31 {
  32   memset (blk, 0, 512);
  33   return rand () & 1 ? (struct H*) blk : 0;
  34 }
  35
  36 int main (void)
  37 {
  38   char blk[512], tmp[512];
  39   struct S *s = (struct S*) blk;
  40   struct H *h;
  41
  42   getblk (blk);
  43
  44   if (s->a  ||  !(h = gethdr (tmp))  ||  s->a != h->d) {
  45
  46     printf ("%d\n", s->b);
  47     if (s->a)
  48       printf ("s->a = %d\n", s->a);
  49     else if (!h)
  50       printf ("!h\n");
  51     else
  52       printf ("h->d = %d\n", h->d);
  53   }
  54 }