gcc/testsuite/gcc.dg/tree-ssa/pr24287.c

   1 /* { dg-do compile } */
   2 /* { dg-options "-O2 -fdump-tree-optimized" } */
   3 int g1(int);
   4 int h(int *a, int *b)__attribute__((pure));
   5 void link_error();
   6
   7 /* The calls to link_error should be eliminated, since nothing escapes to
   8    non-pure functions.  */
   9 int g(void)
  10 {
  11   int t = 0, t1 = 2;
  12   /* ???  That's not true.  The pointers escape to the integer return
  13      value which we do not track in PTA.  */
  14   int t2 = h(&t, &t1);
  15   if (t != 0)
  16     link_error ();
  17   if (t1 != 2)
  18     link_error ();
  19   /* ???  And it would finally escape here even if we did.  */
  20   g1(t2);
  21   if (t != 0)
  22     link_error ();
  23   if (t1 != 2)
  24     link_error ();
  25   return t2 == 2;
  26 }
  27 /* We are allowed to optimize the first two link_error calls.  */
  28 /* { dg-final { scan-tree-dump-times "link_error" 2 "optimized" } } */