[EMAIL PROTECTED] (Paul Jarc) writes:
> Richard Neill <[EMAIL PROTECTED]> wrote:
>> I thought testing for overflow was quite simple?
>> Isn't it just a case of looking at the carry-bit, and seeing whether it
>> gets set?
>
> That's usually how it's done in assembly. In C, it's somewhat more
> compilcated. For example:
> result=a*b;
> if (result/a!=b) { report overflow; }
That won't work, since (signed integer) overflow is undefined in C. A
compiler is allowed to optimize the condition to false.
Andreas.
--
Andreas Schwab, SuSE Labs, [EMAIL PROTECTED]
SuSE Linux Products GmbH, Maxfeldstraße 5, 90409 Nürnberg, Germany
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"And now for something completely different."
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