gcc/testsuite/gcc.dg/Wstrict-overflow-18.c

   1 /* { dg-do compile } */
   2 /* { dg-options "-fstrict-overflow -O2 -Wstrict-overflow" } */
   3
   4 /* Warn about an overflow when folding i > 0, p->a - p->b can be larger
   5    than INT_MAX and thus i can wrap.  */
   6
   7 struct c { unsigned int a; unsigned int b; };
   8 extern void bar (struct c *);
   9 int
  10 foo (struct c *p)
  11 {
  12   int i;
  13   int sum = 0;
  14
  15   for (i = 0; i < p->a - p->b; ++i)
  16     {
  17       /* See PR80511 for the XFAIL.  */
  18       if (i > 0)  /* { dg-warning "signed overflow" "" { xfail *-*-* } } */
  19         sum += 2;
  20       bar (p);
  21     }
  22   return sum;
  23 }