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From: Adam Beneschan <adam@irvine.com>
Newsgroups: comp.lang.ada
Subject: Re: pragma Pack does not work on GNAT 5.01a for Redhat Linux.
Date: Wed, 20 Jun 2007 09:35:58 -0700
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Date: 2007-06-20T09:35:58-07:00
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On Jun 20, 8:51 am, "Bob Spooner" <r...@psu.edu> wrote:

> For exchanging
> binary data between heterogeneous systems, my experience has been that
> record representation clauses are necessary to insure that the data
> representations are identical.

Absolutely.  You can't count on Pack to do things a certain way; the
RM says that the compiler is free to rearrange the components as it
sees fit to make things smaller.  Pack is appropriate when you want
the type to be as small as possible but don't really care how it's
laid out.  It's not appropriate if you care how your record is laid
out; you'll need a record rep clause for that.

                  -- Adam