gcc/testsuite/gcc.c-torture/execute/divconst-2.c

   1 void abort (void);
   2 void exit (int);
   3
   4 long
   5 f (long x)
   6 {
   7   return x / (-0x7fffffffL - 1L);
   8 }
   9
  10 long
  11 r (long x)
  12 {
  13   return x % (-0x7fffffffL - 1L);
  14 }
  15
  16 /* Since we have a negative divisor, this equation must hold for the
  17    results of / and %; no specific results are guaranteed.  */
  18 long
  19 std_eqn (long num, long denom, long quot, long rem)
  20 {
  21   /* For completeness, a check for "ABS (rem) < ABS (denom)" belongs here,
  22      but causes trouble on 32-bit machines and isn't worthwhile.  */
  23   return quot * (-0x7fffffffL - 1L) + rem == num;
  24 }
  25
  26 long nums[] =
  27 {
  28   -1L, 0x7fffffffL, -0x7fffffffL - 1L
  29 };
  30
  31 int
  32 main (void)
  33 {
  34   int i;
  35
  36   for (i = 0;
  37        i < sizeof (nums) / sizeof (nums[0]);
  38        i++)
  39     if (std_eqn (nums[i], -0x7fffffffL - 1L, f (nums[i]), r (nums[i])) == 0)
  40       abort ();
  41
  42   exit (0);
  43 }