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Re: [patch] for PR17474
On Mon, 2004-09-20 at 16:13, Zdenek Dvorak wrote:
> Hello,
>
> > > this handles just the cases when the base variable does not have
> > > a type memory tag; in such case the variable itself acts as an
> > > operand in VUSES/VDEFS (well -- I guess; it seems to work this way...)
> > >
> > If the base variable didn't have an alias tag already, something is
> > _very_ wrong. The base variable is dereferenced, so it must have a tag
> > (either type or name). If that's not the case, the only graceful thing
> > you can do here is ICE.
>
> then you are going to ICE very often. For example in the following
> program
>
> int arr[100];
>
> void xxx(void)
> {
> int i;
>
> for (i = 0; i < 100; i++)
> arr[i] = i;
> }
>
> arr does not have type memory tag (well, did not have in time I wrote
> this piece of code few months ago; perhaps this changed since then?)
>
arr is not a pointer. Of course it doesn't have a tag. That function
should only try to copy aliasing information out of pointers (I had the
impression that this function only takes care of pointer dereferences).
Diego.