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From: sjw <simon.j.wright@mac.com>
Newsgroups: comp.lang.ada
Subject: Re: Gem 39 - compiler specific?
Date: Fri, 4 Sep 2009 15:41:43 -0700 (PDT)
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Date: 2009-09-04T15:41:43-07:00
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On Sep 4, 1:07=A0pm, Maciej Sobczak <see.my.homep...@gmail.com> wrote:

> I have done it very recently and I used
> System.Address_To_Access_Conversions. The access values to genuine Ada
> objects (even of class-wide types) are converted to addresses and
> handed to the C++ component, which at some later point in time calls
> back into Ada providing the previously stored address that Ada
> converts to the original access value.
>
> A very important part of this business is that the C++ component
> *never* uses the given address in any other way than to remember it.
> It is just a "cookie".

Then I don't quite see why you needed to convert at all?

   procedure P (Q : Fancy_Access);
   pragma Import (C, Q);

Or is it that the size of a Fancy_Access makes it hard to represent on
the C side?