gcc/testsuite/gcc.c-torture/execute/ieee/mzero5.c

   1 /* Test gcse handling of IEEE 0/-0 rules.  */
   2 void abort (void);
   3 static double zero = 0.0;
   4
   5 int
   6 negzero_check (double d)
   7 {
   8   if (d == 0)
   9     return !!__builtin_memcmp ((void *)&zero, (void *)&d, sizeof (double));
  10   return 0;
  11 }
  12
  13 int
  14 sub (double d, double e)
  15 {
  16   if (d == 0.0 && e == 0.0
  17       && negzero_check (d) == 0 && negzero_check (e) == 0)
  18     return 1;
  19   else
  20     return 0;
  21 }
  22
  23 int
  24 main (void)
  25 {
  26   double minus_zero = -0.0;
  27   if (sub (minus_zero, 0))
  28     abort ();
  29   return 0;
  30 }