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From: dlw@odi.com (Dan Weinreb)
Newsgroups: comp.lang.c++
Subject: Re: I/O problem
Message-ID: <1990Nov4.230645.10641@odi.com>
Date: 4 Nov 90 23:06:45 GMT
References: <1179@appli.se>
Reply-To: dlw@odi.com
Organization: Object Design, Inc.
Lines: 10
In-Reply-To: niklas@appli.se's message of 3 Nov 90 11:26:27 GMT

In article <1179@appli.se> niklas@appli.se (Niklas Hallqvist) writes:

   And what happens here?  Aha, the vtbl pointer gets saved along with the
   binary image, and will be read in by other programs using the get function.
   No harm in that, is it?  Well, YES!!!!  Another program would be differently
   laid out in memory and the vtbl ptr would not be valid there.  Unpredictable
   results will follow the first virtual call. 

Notice that there's an even worse problem if any of your classes
contain pointer-valued data members.