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Re: basic VRP min/max range overflow question
- From: Paul Schlie <schlie at comcast dot net>
- To: "Joseph S. Myers" <joseph at codesourcery dot com>
- Cc: Dale Johannesen <dalej at apple dot com>,Robert Dewar <dewar at adacore dot com>,Mike Stump <mrs at apple dot com>,Andrew Pinski <pinskia at physics dot uc dot edu>,GCC Development <gcc at gcc dot gnu dot org>
- Date: Sat, 18 Jun 2005 15:16:16 -0400
- Subject: Re: basic VRP min/max range overflow question
> From: "Joseph S. Myers" <joseph@codesourcery.com>
> "no requirements" means that *any* translation conforms in the case of
> undefined behavior. Only those executions not involving undefined
> behavior have any requirements.
What delineates the bounds between undefined and non-undefined behaviors?
(As in the extreme if an undefined behavior may arbitrarily corrupt the
entire specified program state, and/or modify the languages otherwise
required semantics governing the translation/execution of a program, it
would seem that rather than attempting to utilize undefined behaviors as
a basis of optimizations, the compiler should more properly simply abort
compilation upon their detection, as the resulting program would be
otherwise be arguably useless for any likely purpose if the effect of an
undefined behavior within a program is not bounded?)