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From: Paul Mackerras <paulus@samba.org>
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Date: Sat, 5 Jan 2002 09:14:38 +1100 (EST)
To: Florian Weimer <fw@deneb.enyo.de>
Cc: Momchil Velikov <velco@fadata.bg>, Tom Rini <trini@kernel.crashing.org>,
        linux-kernel@vger.kernel.org, gcc@gcc.gnu.org,
        linuxppc-dev@lists.linuxppc.org
Subject: Re: [PATCH] C undefined behavior fix
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Florian Weimer writes:

> Paul Mackerras <paulus@samba.org> writes:
> 
> > One of the reasons why C is a good language for the kernel is that its
> > memory model is a good match to the memory organization used by the
> > processors that linux runs on.  Thus, for these processors, adding an
> > offset to a pointer is in fact simply an arithmetic addition.
> 
> But this is not the memory model of C!  Adding an offset to a pointer
> is an operation involving objects defined by the C language, and not
> machine registers.  Sometimes, this makes a noticeable difference.

Sorry, you are correct.  I should have written "One of the reasons why
C used to be a good language for writing operating system kernels ..."

Paul.
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