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From: Tim Rentsch <tr.17687@z991.linuxsc.com>
Newsgroups: comp.lang.c
Subject: Re: A thought of C
Date: Tue, 21 Apr 2026 21:04:30 -0700
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Xref: csiph.com comp.lang.c:397776

Keith Thompson <Keith.S.Thompson+u@gmail.com> writes:

> David Brown <david.brown@hesbynett.no> writes:
> [...]
>
>> You seem to think that just writing "int a;" somehow creates an int
>> object called "a" along with a slot on the stack or a dedicated
>> register.  That does not happen in many compilers.  And it does not
>> happen in the C semantics.  "a" is an lvalue that /potentially/
>> designates an object - for an uninitialised local variable, it does
>> not designate an object until a value is assigned.
>
> [...]
>
> I don't think that's correct.

In fact, it's wrong.  Encountering a declaration 'int a;' certainly
means that in the abstract machine there is an object corresponding
to the identifier 'a'.

> Within the scope of a declaration `int a;` the expression `a` is
> an lvalue that *does* designate an object.

And more than that:  in the abstract machine an object corresponding
to the identifier 'a' comes into existence as soon as the block
containing 'int a;' is entered, regardless of whether 'a' is
initialized or referenced in any way.