[sa]: Revert partial def stuff, use fake variables instead

Daniel Berlin dberlin@dberlin.org
Mon Dec 20 15:01:00 GMT 2004



On Mon, 20 Dec 2004, Zdenek Dvorak wrote:

> Hello,
>
>>> which seems terribly wrong to me.  Why should I need to change anything
>>> so complicated, when I did not make any change that should affect
>>> results of alias analysis?
>>>
>> You *have* changed the results of alias analysis.  You are introducing a
>> new pointer, assigning it a new address and dereferencing it.
>
> and what?  I am accessing exactly the same location in memory, so from
> the point of *results* of the alias analysis nothing changes.
>
Yes, but you need to keep the data structures up to date to say this, or 
else how do we know this?


> Yes, if the alias analysis is rerun afterwards, it needs to know about
> things like pointers and such, internally.  But the results of the alias
> analysis are not affected by the way addresses are expressed, and having
> to perform magic just to keep the results the same does not seem right
> to me.

What exactly are you proposing you should have to do in order for 
everything else to know you haven't changed anything?

>
> Zdenek
>



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