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From: Maciej Sobczak <see.my.homepage@gmail.com>
Newsgroups: comp.lang.ada
Subject: Re: Dispatching callback handed over to C
Date: Fri, 6 Apr 2012 00:30:31 -0700 (PDT)
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Date: 2012-04-06T00:30:31-07:00
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On 5 Kwi, 11:13, Natasha Kerensikova <lithium...@gmail.com> wrote:

> So for my binding, what about something like=A0:
>
> =A0 =A0type Opaque_Data is null record;
> =A0 =A0pragma Convention (C, Opaque_Data);
>
> =A0 =A0type Opaque_Pointer is access all Opaque_Data;
> =A0 =A0pragma Convention (C, Opaque_Pointer);
[...]

Looks good!

> As far as I cen tell, Opaque_Pointer refers only to types compatibles
> with C,

> Or is there some trap in the above code that I'm missing?

That according to AARM, the C counterpart needs to correspond to
Opaque_Data, that is, a pointer to an empty struct with the same
alignment requirements.

But in general, this seems to be the most convincng solution.

--
Maciej Sobczak * http://www.inspirel.com