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Re: basic VRP min/max range overflow question
- From: Robert Dewar <dewar at adacore dot com>
- To: Michael Veksler <VEKSLER at il dot ibm dot com>
- Cc: Paul Schlie <schlie at comcast dot net>, Dale Johannesen <dalej at apple dot com>, GCC Development <gcc at gcc dot gnu dot org>,"Joseph S. Myers" <joseph at codesourcery dot com>, Mike Stump <mrs at apple dot com>, Andrew Pinski <pinskia at physics dot uc dot edu>
- Date: Mon, 20 Jun 2005 08:44:22 -0400
- Subject: Re: basic VRP min/max range overflow question
- References: <OF7D207586.015359DC-ON43257026.003E4C62-43257026.00441417@il.ibm.com>
Michael Veksler wrote:
Getting a consistent definition of "bounded side-effects"
is a nontrivial task. Simply hacking and patching the
definition does not work. Trust me, I've been there done
that, got burnt and are still paying for my sins.
Indeed! I think anyone who has been involved in the arduous
work of formal language definition is very aware of this. At
one point people designing Ada wanted to make functions side
effect free, we quickly discovered this was not useful since
a useful definition could not be formalized (e.g. is a pure
function that works by using a memo table side effect free?)