Re: Having fun with the following C code (UB)

[Vincent Lefevre <vincent@vinc17.net>]

On 2014-04-15 21:57:21 +0100, Roger Lynn wrote:
> The purpose of this gcc warning isn't to warn you that overflow
> might happen, but to warn you when gcc's optimisations have broken
> any two's complement overflow behaviour that you might have
> expected. Thus if you have written code that assumes "normal" two's
> complement overflow you get a warning when it has been broken by
> assumptions made by the optimiser. In other cases you get "normal"
> overflow so there is no need for this warning.

Thanks for the explanations. So, those whose intent is to follow the
C standard don't need / don't want this warning.

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Vincent Lefèvre <vincent@vinc17.net> - Web: <https://www.vinc17.net/>
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