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From: tmoran@acm.org
Newsgroups: comp.lang.ada
Subject: Re: Should representation clauses be complete for each bit?
Date: Sat, 23 Jul 2011 02:16:32 +0000 (UTC)
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Date: 2011-07-23T02:16:32+00:00
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>  type T is
>     record
>        ...
>        Gap1 : Bits2 := 0; -- must be zero

In Claw.Bitmaps there's a record with

    type Windows_Info is record
        ...
        Planes   : Claw.Word range 1 .. 1 := 1;

IIRC we noticed that we definitely needed the representation

        Planes      at 12 range 0 .. 15;

otherwise ObjectAda didn't leave any space, since it knew that Planes
was a constant always equal to 1.