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Re: Miscompilation of remainder expressions

From: Vincent Lefevre <vincent+gcc at vinc17 dot org>
To: gcc at gcc dot gnu dot org
Date: Wed, 17 Jan 2007 00:38:04 +0100
Subject: Re: Miscompilation of remainder expressions
References: <45AB8770.5040402@cs.unipr.it> <45AD0BD4.9090809@adacore.com> <20070116210356.GS10583@prunille.vinc17.org> <45AD3EC2.2060007@avtrex.com>

On 2007-01-16 13:08:18 -0800, David Daney wrote:
> The difference is that your program didn't get killed by SIGFPE, it
> just gave incorrect results.

An incorrect result is worse, but being killed by SIGFPE is still very
bad.

But I was mainly answering the claim "hard to believe this case appears
in real code". IMHO, INT_MIN % -1 can appear just as 0 + LONG_MIN can
appear, just as LONG_MIN / 1 can appear.

-- 
Vincent Lefèvre <vincent@vinc17.org> - Web: <http://www.vinc17.org/>
100% accessible validated (X)HTML - Blog: <http://www.vinc17.org/blog/>
Work: CR INRIA - computer arithmetic / Arenaire project (LIP, ENS-Lyon)

References:
- Miscompilation of remainder expressions
  - From: Roberto Bagnara
- Re: Miscompilation of remainder expressions
  - From: Robert Dewar
- Re: Miscompilation of remainder expressions
  - From: Vincent Lefevre
- Re: Miscompilation of remainder expressions
  - From: David Daney

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