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Date: Tue, 28 Jun 2005 14:33:00 -0000
From: Robert Dewar <dewar@adacore.com>
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To: Gabriel Paubert <paubert@iram.es>
CC: Gabriel Dos Reis <gdr@integrable-solutions.net>, 
 Andrew Pinski <pinskia@physics.uc.edu>,
 gcc mailing list <gcc@gcc.gnu.org>
Subject: Re: signed is undefined and has been since 1992 (in GCC)
References: <27fdc0d8dc588cfdb3a14a153c5d037c@physics.uc.edu> <m3fyv3je0t.fsf@uniton.integrable-solutions.net> <6d9fa260f233e519762c7d11276a35ad@physics.uc.edu> <m3hdfjhxok.fsf@uniton.integrable-solutions.net> <3dbad9a6bd7eb1aea74ff2245eaa1b99@physics.uc.edu> <m3br5rhvgm.fsf@uniton.integrable-solutions.net> <42C115D5.8070503@adacore.com> <m3psu6hfau.fsf@uniton.integrable-solutions.net> <42C13D4D.9040604@adacore.com> <m3d5q6fyrf.fsf@uniton.integrable-solutions.net> <20050628134642.GA18415@iram.es>
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Gabriel Paubert wrote:

> Now in practice what would be the cost of checking that the divisor
> is -1 and take an alternate path that computes the correct 
> results (in modulo arithmetic) for this case ?

We actually had to do this on the x86 early on for GNAT, UGH!