modernc.org/ccgo/v3@v3.16.14/lib/testdata/gcc-9.1.0/gcc/testsuite/gcc.c-torture/execute/pr44683.c (about)

     1  int __attribute__((noinline,noclone))
     2  copysign_bug (double x)
     3  {
     4    if (x != 0.0 && (x * 0.5 == x))
     5      return 1;
     6    if (__builtin_copysign(1.0, x) < 0.0)
     7      return 2;
     8    else
     9      return 3;
    10  }
    11  int main(void)
    12  {
    13    double x = -0.0;
    14    if (copysign_bug (x) != 2)
    15      __builtin_abort ();
    16    return 0;
    17  }
    18