It sounds like you are under the impression that UB simply means you can't trust signed integers to wrap. Unfortunately, it is worse than that; under surprisingly normal-looking conditions, it is not unheard of that the compiler optimises an interation check away and replaces it with constant true or false, depending on what makes the underlying internal represenation neater.

That's way beyond "can't do X"; it's "the meaning of your program suddenly ceases to exist".