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Date: Tue, 28 Jun 2005 20:24:00 -0000
From: Robert Dewar <dewar@adacore.com>
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To: Paul Koning <pkoning@equallogic.com>
CC:  galibert@pobox.com,  dave.korn@artimi.com,  aph@redhat.com, 
 gdr@integrable-solutions.net,  pinskia@physics.uc.edu,  gcc@gcc.gnu.org
Subject: Re: signed is undefined and has been since 1992 (in GCC)
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Paul Koning wrote:

> And also because most people believe that C applies normal computer
> arithmetic, and they believe that normal computer arithmetic is
> wrapped 2's complement.  (And indeed it usually is, give or take some
> bizarre exceptions like MAX_INT % -1)

and not so bizarre exceptions like machines that trap on signed
overflow.
> 
> We all know better, but how tiny is the fraction of C programmers who
> have ever even *seen* the ANSI C spec, much less know in detail what
> it says?

OK, but to me "knows C" (the predicate in my statement) certainly
means being familiar with the standard, not necessarily by reading it,
I am sure there are lots of good books on C that have a good account
of the rules (K&R is clear enough on this particular issue).