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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 08:57:56 -0400
- Subject: Re: basic VRP min/max range overflow question
- References: <OF8C9F9A3B.05532BB9-ON43257026.00446C86-43257026.0046C837@il.ibm.com>
Michael Veksler wrote:
As for overflow, you can say that you want instead of "undefined"
to treat is "unspecified".
In Ada 95 we introduced a new category of behavior, called a bounded
error. We tried to recategorize as many erroneous (= C undefined)
cases as possible to bounded error.
A bounded error is still considered incorrect programming, but the
standard specifies the range of possible results allowed.