It's fascinating that this kind of bug is exactly you can't really avoid even when rust is supposedly to guard against. Rust mitigated this problem a lot in practice, but you can never be certain because of issues like this in practice. This is similar that a math proof that's already been peer reviewed and accepted as truth, may still be possible to be wrong, although the chance is very small but it's not zero. Epseicially when the complexity gets higher.