From mboxrd@z Thu Jan  1 00:00:00 1970
X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me
X-Spam-Level: 
X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00,FREEMAIL_FROM
	autolearn=ham autolearn_force=no version=3.4.4
X-Google-Language: ENGLISH,ASCII-7-bit
X-Google-Thread: 103376,7be3870dd9c9518f
X-Google-Attributes: gid103376,public
X-Google-ArrivalTime: 2002-12-14 14:28:02 PST
Path: 
 archiver1.google.com!news1.google.com!newsfeed.stanford.edu!canoe.uoregon.edu!arclight.uoregon.edu!newsfeed.mathworks.com!btnet-peer0!btnet-peer1!btnet!newsr1.ipcore.viaginterkom.de!newsfeed.stueberl.de!newsfeed01.sul.t-online.de!newsmm00.sul.t-online.com!t-online.de!news.t-online.com!not-for-mail
From: Alfred Hilscher <Alfred.Hilscher@t-online.de>
Newsgroups: comp.lang.ada
Subject: Re: CONSTRAINT_ERROR - why?
Date: Sat, 14 Dec 2002 23:26:19 +0100
Organization: T-Online
Message-ID: <3DFBB00B.230289A2@t-online.de>
References: <3DFB7841.F898C02@t-online.de> <3DFB9276.7070809@acm.org>
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Transfer-Encoding: 7bit
X-Trace: news.t-online.com 1039904868 02 15139 YFm6EjsbSGa3M- 021214 22:27:48
X-Complaints-To: abuse@t-online.com
X-Sender: 320001779794-0001@t-dialin.net
X-Mailer: Mozilla 4.75 [de] (WinNT; U)
X-Accept-Language: de
Xref: archiver1.google.com comp.lang.ada:31830
Date: 2002-12-14T23:26:19+01:00
List-Id: <comp.lang.ada>



Jeffrey Carter schrieb:
> 
> Alfred Hilscher wrote:
> > This program raises exception CONSTRAINT_ERROR for the second
> > assignment. It happens with GNAT 3.13p and 3.14p (on windows).
> >
> > Can someone explain why? Is this a compiler error or do I misunderstand
> > something?
> 
> The reason Constraint_Error is raised is because the code violates a
> constraint.
> 
> Why are you using Interfaces.C if you're not interfacing with C?


I extracted the example from a big (really big) application where heavy
use off (hardware-) manufacturer provided dlls is done.

 
> Since the LHS of your assignment is type Byte, the expression is
> evaluated using
> 
> function "/" (Left, Right : Byte) return Byte;
> 
> The value passed to Left is not in the range of Byte. If you want this
> evaluated as a universal expression, you have to add a step:
> 
> declare
>     Value : constant := X'Size / 8;
> begin
>     Y := Value;
> end;


Is there no way to avoid this extra assignment? I expected something
like function "/" (Left, Right : universal_integer) return Byte;


> --
> Jeff Carter
> "Why don't you bore a hole in yourself and let the sap run out?"
> Horse Feathers