From mboxrd@z Thu Jan  1 00:00:00 1970
From: Al Viro <viro@ftp.linux.org.uk>
Subject: Re: pointer arithmetics and casts
Date: Sat, 26 May 2007 04:43:55 +0100
Message-ID: <20070526034354.GP4095@ftp.linux.org.uk>
References: <20070525212300.GL4095@ftp.linux.org.uk> <118833cc0705251814h9fffa39xc4a0f3f9e61242b9@mail.gmail.com>
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To: Morten Welinder <mwelinder@gmail.com>
Cc: linux-sparse@vger.kernel.org

On Fri, May 25, 2007 at 09:14:33PM -0400, Morten Welinder wrote:
> >        BINOP[+]
> >                <tree for p>
> >                BINOP[*]
> >                        IMPLICIEDT_CAST[ptrdiff_t]
> >                                <tree for i>
> >                        VAL[sizeof(*p)]
> 
> I don't think you want ptrdiff_t there.  It isn't guaranteed to
> be big enough.

Only if you are allowed to have an array object with elements too far
for their addresses to be subtracted...
 
> size_t should do, though.

size_t is an unsigned type, so by definition it won't do...