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To: Andrew Pinski <pinskia@physics.uc.edu>
Cc: Daniel Berlin <dberlin@dberlin.org>, Joe Buck <Joe.Buck@synopsys.COM>,
        "'gcc mailing list'" <gcc@gcc.gnu.org>
Subject: Re: Should GCC publish a general rule/warning due to it's default presumption of undefined signed integer overflow semantics?
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From: Gabriel Dos Reis <gdr@integrable-solutions.net>
In-Reply-To: <c9a4a7ef8c66bbed1f4711fce767a0ea@physics.uc.edu>
Date: Fri, 01 Jul 2005 05:02:00 -0000
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Andrew Pinski <pinskia@physics.uc.edu> writes:

| On Jul 1, 2005, at 12:49 AM, Gabriel Dos Reis wrote:
| 
| >
| > As I said, if you let user tell you that his loop behaves well, i.e.
| > bounds do not rely on wrapping semantics, and yet he writes his loop to
| > deceive the compiler, then he loses.  Let him choose his own poinson,
| > don't think you have to choose it for him.
| 
| They already can, that is what -fwrapv is for.

No, you completely missed the point and it would help if you read
through carefully.  The choice was about letting user tell you what he
knows/assumes about his loop bounds.  Not applying uniformly the
wrapping semantics.  

(Not counting the fact that it was pointed out -fwrapv is useful as is).

-- Gaby