The compiler could still sub in the equation for unsigned integers, the equation is (mostly) the same.
Not discussed (that I can see), the real problem is the loop variable -- because the loop ends with ' <= n', which means if n is the largest unsigned integer, this is an infinite loop. One easy thing UB is useful for is proving these types of loop terminate (as overflowing would be UB).
Not discussed (that I can see), the real problem is the loop variable -- because the loop ends with ' <= n', which means if n is the largest unsigned integer, this is an infinite loop. One easy thing UB is useful for is proving these types of loop terminate (as overflowing would be UB).