I don't understand what you are saying. An overflow in an intermediate result should signal an overflow unless you're relying on some special property of 2's c

I don't understand what you are saying. An overflow in an intermediate result should signal an overflow unless you're relying on some special property of 2's complement arithmetic in which case you should be using specific datatypes to suppress the check. All I'm saying about floating point is that the presence of overflow checking in high performance FPU's falsifies (afaict) the claim that it's unfeasible to do the same thing for integers.