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From: Keith Thompson <kst-u@mib.org>
Newsgroups: comp.lang.c
Subject: Re: usecases of void foo(char **b) {}
Date: Tue, 01 Nov 2016 08:25:15 -0700
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Keith Thompson <kst-u@mib.org> writes:
[...]
> A (valid non-null) pointer is always a pointer to a single object.  That
> single object may or may not be the initial element of an array object.
[...]

Sorry, I missed a couple of cases.  A valid pointer can point just
past the last element of an array object, and a non-null pointer
of pointer-to-function type can point to a function.

And for purposes of pointer arithmetic, a single object is treated
as a element of a single-element array.

So, for example, this sets p to a valid pointer value (which cannot be
derferenced):

    int n;
    int *p = &n + 1;

-- 
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"