Integer overflow and underflow semantics

[Alex Rønne Petersen]

On 07-05-2012 10:05, Don Clugston wrote:
> On 05/05/12 06:57, Alex Rønne Petersen wrote:
>> Hi,
>>
>> I don't think the language really makes it clear whether overflows and
>> underflows are well-defined. Do we guarantee that for any integral type
>> T, T.max + 1 == T.min and T.min - 1 == T.max?
>>
>> This is relevant in particular for GDC and LDC since they target a lot
>> of weird architectures.
>>
>
> I think the reason that C makes no guarantees, was because of
> ones-complement machines (which had become very rare even by 1970).
> Surely we can assume 2-s complement behaviour?

That's what I'm thinking. I can't even name a one's complement machine 
still in use today.

-- 
- Alex