gcc/testsuite/gcc.dg/tree-ssa/ssa-ccp-21.c

   1 /* { dg-do compile } */
   2 /* { dg-options "-O -fdump-tree-ccp1" } */
   3
   4 struct A {
   5     struct B {
   6         int i;
   7     } b;
   8 } a;
   9
  10 int foo (void)
  11 {
  12   struct B *p = &a.b;
  13   struct A *q = (struct A *) p;
  14   return q->b.i;
  15 }
  16
  17 int bar (void)
  18 {
  19   struct A *p = &a;
  20   struct B *q = (struct B *) p;
  21   return q->i;
  22 }
  23
  24 /* The first access is through struct A, so a.b.i is fine,
  25    the second access needs to preserve the original access type struct B.  */
  26
  27 /* { dg-final { scan-tree-dump-times "a.b.i" 1 "ccp1" } } */
  28 /* { dg-final { scan-tree-dump-times "MEM\\\[\\\(struct B \\\*\\\)&a\\\].i" 1 "ccp1" } } */
  29 /* { dg-final { cleanup-tree-dump "ccp1" } } */