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Date: Fri, 12 Oct 2007 12:49:00 -0000
From: "Richard Guenther" <richard.guenther@gmail.com>
To: "Richard Kenner" <kenner@vlsi1.ultra.nyu.edu>
Subject: Re: [PATCH] Fix optimization regression in constant folder
Cc: ebotcazou@adacore.com, gcc-patches@gcc.gnu.org, iant@google.com,  	mark@codesourcery.com, matz@suse.de
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On 10/12/07, Richard Kenner <kenner@vlsi1.ultra.nyu.edu> wrote:
> > We do that all the time now with POINTER_PLUS_EXPR which takes an
> > unsigned sizetype as its offset parameter.  There is nothing bad about this.
>
> It's one thing if we have an expression with an offset that just MIGHT
> be negative, but quite another to do so with an expression that we KNOW
> will be negative, in my opinion.  Does the spec of POINTER_PLUS_EXPR really
> require that its offset parameter be an unsigned type?  It should be
> any sizetype.

It requires that it is exactly 'sizetype'.  Which makes it signed for Ada again.

Richard.