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Re: optimisation question
On Tue, Feb 01, 2005 at 07:39:59PM +0000, Remy Martin wrote:
> >> A sequence point is (more or less) a situation where
> >> the exact order of execution/evaluation is undefined, no?
> >
> > Au contraire!
>
> ?! I see:
>
> "The C standard is worded confusingly, therefore there is some debate over
> the precise meaning of the sequence point rules in subtle cases."
No, you don't see; there is no confusion in the C standard on the example
you cited. The phrase "Au contraire" (on the contrary) was used because
you have the meaning exactly backwards, it is sequence points that
*specify* the order of evaluation (though an alternative order is legal if
it is guaranteed to produce the same result). If there are no sequence
points between two potentially colliding side effects, *then* the result
is undefined.