Function compare_int_f64 

pub fn compare_int_f64(x: i64, y: f64) -> Ordering

Exact Int↔Float comparison (design 226 §5.1): compare mathematical values, with the two total_cmp placements preserved bit-for-bit so no existing data reorders — Int(i) carries +0.0’s sign (Int(0) > Float(-0.0)), and NaNs keep their total_cmp positions (-NaN below every Int, +NaN above).

Never widens x through as f64: above 2^53 that rounding made two distinct Ints compare Equal to the same Float (a non-transitive relation — §3), which is exactly the silent-wrong-rows failure this replaces.