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Re: [PATCH] Document arithmetic overflow semantics

From: "Joseph S. Myers" <jsm28 at cam dot ac dot uk>
To: Fergus Henderson <fjh at cs dot mu dot OZ dot AU>
Cc: <gcc at gcc dot gnu dot org>
Date: Fri, 14 Feb 2003 18:59:17 +0000 (GMT)
Subject: Re: [PATCH] Document arithmetic overflow semantics

On Fri, 14 Feb 2003, Fergus Henderson wrote:

> Even for C, it might make sense to have a compilation option in which
> C operations were mapped to "op dont_care" rather than "op undef".
> This would be useful for compiling security-critical software.
> Perhaps it should even be the default.

I think we should recommend using "op trap" for security-critical
software.  There is more runtime cost, but if an overflow does occur and
isn't trapped it is very likely to be an exploitable security hole.

-- 
Joseph S. Myers
jsm28@cam.ac.uk

References:
- Re: [PATCH] Document arithmetic overflow semantics
  - From: Fergus Henderson

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