Re: List of optimizations enabled by -O1 seems incorrect

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Andrew Haley wrote:

> gcc looks at
> 
>   if (!foo && !bar)
>     ...
> 
> and turns it into
> 
>   if (foo|bar)
>     goto x;
>   ...
>  x:
> 
> So, from Valgrind's point of view, the branch depends on the value of
> bar, which is uninitialized.  We know that if foo is nonzero there is
> no such dependency, but Valgrind would have to do some heavyweight
> dependency analysis to figure that one out.

Ding-ding-ding... and the winner is, I'm not awake enough yet this
morning :-) Thanks for the explanation!

-- 
Kevin P. Fleming
Digium, Inc. | Director of Software Technologies
445 Jan Davis Drive NW - Huntsville, AL 35806 - USA
skype: kpfleming | jabber: kpfleming@xxxxxxxxxx
Check us out at www.digium.com & www.asterisk.org

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