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From: Victor Porton <porton@narod.ru>
Newsgroups: comp.lang.ada
Subject: Re: Unchecked_Union record inside an other record - trouble
Date: Fri, 08 Aug 2014 19:56:15 +0300
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Date: 2014-08-08T19:56:15+03:00
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Adam Beneschan wrote:

> On Friday, August 8, 2014 8:36:48 AM UTC-7, Victor Porton wrote:
>> I am trying to interface my program with a C library.
> 
>> The below program does not compile:
>> main.adb:19:14: unconstrained subtype in component declaration
> 
>> If this does not work, what should I do to interface a union inside a
>> struct in a C library?
> 
>> -- main.adb
>> 
>> with Interfaces.C; use Interfaces.C;
> 
>> procedure Main is
> 
>>    type Kind is (First, Second);
>  
>>    type T(K: Kind) is
> 
> change this to
> 
>      type T(K: Kind := Kind'First) is

Done.

But it is a hack.

I propose to change ARM not to require a discriminant in this specific case 
(Unchecked_Union).

-- 
Victor Porton - http://portonvictor.org