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From: Adam Beneschan <adam@irvine.com>
Newsgroups: comp.lang.ada
Subject: Re: not null
Date: Wed, 4 Mar 2009 08:16:25 -0800 (PST)
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Date: 2009-03-04T08:16:25-08:00
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On Mar 4, 7:22 am, Georg Bauhaus <rm.dash-bauh...@futureapps.de>
wrote:

> The overall impact of refs not "attached" (to use
> an Eiffel term; not null is spreading through languages
> it seems; C++, too?) is a financial disaster, with
> possibly one exception: there is money in a business
> selling software components whose purpose is to guard
> the holes kept open by operating system sellers.
>
> (Antivirus etc.)

Is there any basis for this last comment?  I've seen lots of reports
of vulnerabilities caused by buffer overflows combined with lack of
range checking, and by double-deallocation errors (deallocating the
same chunk of memory twice and making hash of your heap structures),
but I don't recall seeing any caused by null references.  Errors
involving null references seem a lot more likely just to make programs
die unexpectedly, than to allow arbitrary code execution or the like.

                                 -- Adam