gcc/testsuite/gcc.dg/c90-const-expr-3.c

   1 /* Test for constant expressions: broken optimization with const variables.  */
   2 /* Reference: ISO 9989:1990 6.5.15 */
   3 /* Origin: Joseph Myers <jsm28@cam.ac.uk> */
   4 /* { dg-do compile } */
   5 /* { dg-options "-std=iso9899:1990 -O2" } */
   6 /* Note: not using -pedantic since the -std option alone should be enough
   7    to give the correct behavior to conforming programs.  */
   8
   9 static const int ZERO = 0;
  10 static const double DZERO = 0;
  11
  12 int *a;
  13 int b;
  14 long *c;
  15
  16 /* Assertion that n is a constant zero: so the conditional expression
  17    has type 'int *' instead of 'void *'.
  18 */
  19 #define ASSERT_NPC(n)   (b = *(1 ? a : (n)))
  20 /* Assertion that n is not a constant zero: so the conditional
  21    expressions has type 'void *' instead of 'int *'.
  22 */
  23 #define ASSERT_NOT_NPC(n)       (c = (1 ? a : (void *)(__SIZE_TYPE__)(n)))
  24
  25 void
  26 foo (void)
  27 {
  28   ASSERT_NPC (0);
  29   ASSERT_NOT_NPC (ZERO);
  30   ASSERT_NPC (0 + 0);
  31   ASSERT_NOT_NPC (ZERO + 0); /* { dg-bogus "incompatible" "bogus null pointer constant" } */
  32   ASSERT_NOT_NPC (ZERO + ZERO); /* { dg-bogus "incompatible" "bogus null pointer constant" } */
  33   ASSERT_NPC (+0);
  34   ASSERT_NOT_NPC (+ZERO); /* { dg-bogus "incompatible" "bogus null pointer constant" } */
  35   ASSERT_NPC (-0);
  36   ASSERT_NOT_NPC (-ZERO); /* { dg-bogus "incompatible" "bogus null pointer constant" } */
  37   ASSERT_NPC ((char) 0);
  38   ASSERT_NOT_NPC ((char) ZERO);
  39   ASSERT_NPC ((int) 0);
  40   ASSERT_NOT_NPC ((int) ZERO);
  41   ASSERT_NPC ((int) 0.0);
  42   ASSERT_NOT_NPC ((int) DZERO);
  43   ASSERT_NOT_NPC ((int) +0.0); /* { dg-bogus "incompatible" "bogus null pointer constant" } */
  44   ASSERT_NOT_NPC ((int) (0.0+0.0)); /* { dg-bogus "incompatible" "bogus null pointer constant" } */
  45   ASSERT_NOT_NPC ((int) (double)0.0); /* { dg-bogus "incompatible" "bogus null pointer constant" } */
  46 }