Function copysign_bug

test/core/test_negative_zero.c:12–27

test copysign of 0

// test copysign of 0
int __attribute__((noinline))
copysign_bug (double x)
{
  if (x != 0.0 && (x * 0.5 == x)) {
    printf("1\n");
    return 1;
  }
  printf("f: %f\n", x);
  if (__builtin_copysign(1.0, x) < 0.0) {
    printf("2\n");
    return 2;
  } else {
    printf("3\n");
    return 3;
  }
}

int main() {
#define TEST(x, y) printf("%.2f, %.2f ==> %.2f\n", x, y, copysign(x, y));