gcc/testsuite/gcc.dg/tree-ssa/20040319-1.c

   1 /* { dg-do run } */
   2 /* { dg-options "-O2" } */
   3
   4 /* Test derived from PR 14643.  When a function has no addressable
   5    variables but 2 or more pointers have conflicting memory tags, they
   6    were not being processed by the type based alias analyzer,
   7    resulting in optimizations removing a non-redundant load.  */
   8
   9 extern void abort (void);
  10
  11 struct bar { int count;  int *arr;};
  12
  13 void foo (struct bar *b)
  14 {
  15   b->count = 0;
  16   *(b->arr) = 2;
  17   if (b->count == 0)    /* b->count can't be assumed to be 0 here.  */
  18     abort ();
  19 }
  20
  21 int
  22 main ()
  23 {
  24   struct bar x;
  25   x.arr = &x.count;
  26   foo (&x);
  27   return 0;
  28 }