From mboxrd@z Thu Jan  1 00:00:00 1970
X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me
X-Spam-Level: 
X-Spam-Status: No, score=0.4 required=5.0 tests=BAYES_00,FORGED_MUA_MOZILLA
	autolearn=no autolearn_force=no version=3.4.4
X-Google-Thread: a07f3367d7,12a7e74c384c0acb
X-Google-Attributes: gida07f3367d7,public,usenet
X-Google-NewGroupId: yes
X-Google-Language: ENGLISH,ASCII-7-bit
Received: by 10.66.81.98 with SMTP id z2mr1183812pax.19.1349312550793;
        Wed, 03 Oct 2012 18:02:30 -0700 (PDT)
Path: 
 t10ni23610462pbh.0!nntp.google.com!border1.nntp.dca.giganews.com!border4.nntp.dca.giganews.com!border2.nntp.dca.giganews.com!nntp.giganews.com!novia!news-hub.siol.net!news.mi.ras.ru!goblin-spool!goblin2!goblin.stu.neva.ru!news.neu.edu.cn!newsgate.cuhk.edu.hk!news.netfront.net!not-for-mail
From: Jeffrey Carter <spam.jrcarter.not@spam.not.acm.org>
Newsgroups: comp.lang.ada
Subject: Re: optimization away of checks in 'valid
Date: Wed, 26 Sep 2012 09:46:42 -0700
Organization: Also freenews.netfront.net; news.tornevall.net
Message-ID: <k3vbhi$2g1r$1@adenine.netfront.net>
References: <5a0711d8-81ad-4200-9b6e-a80feffd5302@googlegroups.com>
 <b1b0d2a4-2b35-43e8-8ce5-506ff112b189@googlegroups.com>
NNTP-Posting-Host: 184.20.60.112
Mime-Version: 1.0
X-Trace: adenine.netfront.net 1348678004 81979 184.20.60.112 (26 Sep 2012
 16:46:44 GMT)
X-Complaints-To: news@netfront.net
NNTP-Posting-Date: Wed, 26 Sep 2012 16:46:44 +0000 (UTC)
User-Agent: Mozilla/5.0 (X11; Linux x86_64;
 rv:15.0) Gecko/20120827 Thunderbird/15.0
In-Reply-To: <b1b0d2a4-2b35-43e8-8ce5-506ff112b189@googlegroups.com>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding: 7bit
Date: 2012-09-26T09:46:42-07:00
List-Id: <comp.lang.ada>

Joseph Wisniewski wrote on comp.lang.ada:
> we had a case where C++ code was not checking the bounds of a
> integer subtype as it was passed to Ada code via a function
> parameter. The Ada code _was_ checking via 'valid. 'valid returned
> true even though the integer value was out of bounds. Turns out the
> compiler relied on the "allowed assumption" that all callers "check
> their bounds" for such data.

Using any scalar subtype other than those in Interfaces.C when interfacing to 
C/++ is asking for trouble.

-- 
Jeff Carter
"Sons of a silly person."
Monty Python & the Holy Grail
02

--- news://freenews.netfront.net/ - complaints: news@netfront.net ---