c++/1689: dynamic_cast operator is wrong

[Jorgen dot Sigvardsson at kau dot se]

>Number:         1689
>Category:       c++
>Synopsis:       dynamic_cast operator is wrong
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Jan 18 01:16:00 PST 2001
>Closed-Date:
>Last-Modified:
>Originator:     ?
>Release:        gcc version 2.95.2 20000220 (Debian GNU/Linux)
>Organization:
>Environment:
Debian GNU/Linux (Unstable)
>Description:
dynamic_cast does not allow me to do simple casts, which are to my knowledge allowed by the C++ language.

I have also been able to reproduce the error on http://www.codesourcery.com/gcc-compile.shtml where the compile output explicitly tells me that source type is not polymorphic. More on the actual problem in thw "How-To-Repeat" field.

I noticed this error in a larger project which I am working on. I am not sending you that source since it is quite big and because of the fact I can reproduce the error in just a few lines of code. 
>How-To-Repeat:
Just compile this file with g++.
>Fix:
I don't have the slightest idea.. I would assume that some magic should be done to the type information management in the compiler ;-)
>Release-Note:
>Audit-Trail:
>Unformatted:
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