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From: Keith Thompson <kst-u@mib.org>
Newsgroups: comp.lang.c
Subject: Re: C Programming Tutorial on Youtube
Date: Tue, 11 Oct 2016 12:18:37 -0700
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ram@zedat.fu-berlin.de (Stefan Ram) writes:
> supercat@casperkitty.com writes:
>>Whether *any* pointer represents any kind of address is an implementation
>
>   The null pointer might be called an "address constant".
>
>       »An address constant is a null pointer, a pointer to an
>       lvalue designating an object of static storage duration,
>       or a pointer to a function designator«, 6.6.p9
>
>   This says that an address constant can be a null pointer.
>
>   Read from the right to the left, it says that a null 
>   pointer is an address constant.
>
>   I think it's safe to say that an address constant is an address.
>   So a null pointer is an address.
>   It is just not an address /of an object/.

That section is badly worded in my opinion.  An "address constant" is a
source code construct.  A "null pointer" is a runtime value.

It's clear enough that at least `(void*)0` is an "address constant".  I
suppose it's therefore reasonable to infer that a null pointer value is
an "address".  I'd be more comfortable with that conclusion if it were
stated more clearly.

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Working, but not speaking, for JetHead Development, Inc.
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"