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From: "Alex R. Mosteo" <alejandro@mosteo.com>
Newsgroups: comp.lang.ada
Subject: Re: Issue with GNAT GPL 2009 and GtkAda
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Date: Fri, 26 Jun 2009 10:39:45 +0200
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Date: 2009-06-26T10:39:45+02:00
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Dmitry A. Kazakov wrote:

> On Thu, 25 Jun 2009 05:06:08 -0400, Stephen Leake wrote:
> 
>> Another thought: whenever I have trouble with anonymous access types,
>> I replace them with the corresponding named access type, and the
>> problem goes away. That may indicate a conmpiler bug, but I've always
>> had to much to do to find out.
> 
> Yes, but that is not necessarily a compiler bug. It is quite simple to
> create a serious problem to oneself:
> 
> declare
>    Ptr : access T := new T;
> begin
>    ...
>    External_Ptr := Ptr.all'Uchecked_Access; -- Copy the pointer
>    ...
> end;  -- Now External_Ptr is dangling, because the object is freed.
 
If I understand correctly, this is because the type of Ptr goes out of 
scope?

I strongly suspect that Gnat does not behave this way, but I should test it.