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Date: Fri, 13 Sep 2002 00:36:00 -0000
From: "Maciej W. Rozycki" <macro@ds2.pg.gda.pl>
Reply-To: "Maciej W. Rozycki" <macro@ds2.pg.gda.pl>
To: Daniel Jacobowitz <drow@mvista.com>
cc: Andrew Cagney <ac131313@ges.redhat.com>, Fred Fish <fnf@intrinsity.com>,
        binutils@sources.redhat.com, gdb@sources.redhat.com
Subject: Re: MIPS sign extension of addresses
In-Reply-To: <20020912153000.GA11343@nevyn.them.org>
Message-ID: <Pine.GSO.3.96.1020913092432.21615A-100000@delta.ds2.pg.gda.pl>
Organization: Technical University of Gdansk
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On Thu, 12 Sep 2002, Daniel Jacobowitz wrote:

> > >I've not yet checked, but are there fundamental reasons why bfd_vma
> > >or CORE_ADDR have to be unsigned?
> > 
> > I don't think it will help.  I think it will also hinder the situtation 
> > where BFD/GDB are supporting multiple architectures - one signed and one 
> > unsigned.
> 
> Oh, Andrew's right.  Signed CORE_ADDR isn't viable because other
> architectures have and assume an unsigned address space.

 Because MIPS is a minority?  Well, I can see some reason here, but care
has to be taken not to lose a sign with casts when operating on MIPS
addresses.  Fortunately the positive and the negative ranges of addresses
are distinct on MIPS so you won't find normal code or data crossing a
boundary (that might lead to wrong results of compare operations).

-- 
+  Maciej W. Rozycki, Technical University of Gdansk, Poland   +
+--------------------------------------------------------------+
+        e-mail: macro@ds2.pg.gda.pl, PGP key available        +