gcc/testsuite/gcc.dg/pr23584.c

   1 /* Regression test for PR middle-end/23584 */
   2 /* Verify that dereferencing an absolute address inside of a function
   3    makes that function impure.  */
   4
   5 /* { dg-do compile } */
   6 /* { dg-options "-O1 -fdump-ipa-pure-const" } */
   7
   8 int test1 (void)
   9 {
  10   return * (volatile int *) 0x1234;
  11 }
  12
  13 int test2 (void)
  14 {
  15   int local = * (volatile int *) 0x1234;
  16   return local;
  17 }
  18
  19 /* { dg-final { scan-ipa-dump-not "found to be pure: test1" "pure-const" } } */
  20 /* { dg-final { scan-ipa-dump-not "found to be pure: test2" "pure-const" } } */
  21 /* { dg-final { cleanup-ipa-dump "pure-const" } } */