hash

static VALUE
flo_hash(VALUE num)
{
    double d;
    st_index_t hash;

    d = RFLOAT_VALUE(num);
    /* normalize -0.0 to 0.0 */
    if (d == 0.0) d = 0.0;
    hash = rb_memhash(&d, sizeof(d));
    return LONG2FIX(hash);
}