zack's todo list
Florian Weimer
Florian.Weimer@RUS.Uni-Stuttgart.DE
Thu Nov 16 03:09:00 GMT 2000
Mike Stump <mrs@windriver.com> writes:
> 6.1.2.2 Linkages of identifiers
> Identifiers with no linkage denote unique entities.
>
> So, this would seem to indicate what their thinking was. It is the
> words `unique entity' that seems to mandates the requirement of unique
> address, I think.
Hmm, I think so. Thanks.
(BTW, which version of the standard are you quoting?)
> > -- for an object, causes storage to be reserved for that
> > object;
>
> > The second declaration (or the first, depending on your view) does
> > not "cause storage to be reserved for that object", thus violating
> > the standard.
>
> The phrase causes storage to be reserved, doesn't mean that it causes
> storage to be reserved. This is a fundamental misunderstanding of
> Standadeze. It is only that one isn't allowed to notice that storage
> isn't reserved, but if you don't, or cannot, then you cannot observe
> it, and if you cannot observe it, it is rather meaningless.
Yes, of course. (Reusing stack locations for different variables with
non-overlapping usage is a common example of this practice.) But
gcc.dg/c99-func-3.c reveals a difference---and the code does not
trigger undefined or implementation-defined behavior; so the compiler
is not permitted to make any optimizations in this case.
--
Florian Weimer Florian.Weimer@RUS.Uni-Stuttgart.DE
University of Stuttgart http://cert.uni-stuttgart.de/
RUS-CERT +49-711-685-5973/fax +49-711-685-5898
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