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From: Jeffrey Carter <spam.jrcarter.not@spam.not.acm.org>
Newsgroups: comp.lang.ada
Subject: Re: Warning: Storage error
Date: Sat, 09 Aug 2014 09:08:54 -0700
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Xref: news.eternal-september.org comp.lang.ada:21611
Date: 2014-08-09T09:08:54-07:00
List-Id: <comp.lang.ada>

On 08/09/2014 08:20 AM, Victor Porton wrote:
>     type My_String (Length: Integer := 0) is
>        record
>           Str: String(1..Length);
>        end record;
>
> warning: creation of "My_String" object may raise Storage_Error
>
> Why this warning?

There are 2 ways to implement such a type. One allocates just as much space as 
the current value (plus some small fixed overhead); the other allocates enough 
space for the largest value.

Some argue that Ichbiah intended the former, and there is at least one compiler 
that does it that way. It appears that you're using a compiler that uses the 
latter, and every such object will take at least Integer'Last bytes.

It also appears that you're attempting to reinvent Ada.Strings.Bounded.

-- 
Jeff Carter
"Insufficient laughter--that's grounds for divorce."
Play It Again, Sam
126