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From: "Randy Brukardt" <randy@rrsoftware.com>
Newsgroups: comp.lang.ada
Subject: Re: pragma Pack vs. Convention C, portability issue?
Date: Fri, 11 Jan 2008 22:58:47 -0600
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Date: 2008-01-11T22:58:47-06:00
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"(see below)" <yaldnif.w@blueyonder.co.uk> wrote in message
news:C3AD79A1.D95EF%yaldnif.w@blueyonder.co.uk...
...
> What is the view on combinations like this:
>
>    type seive is array (pos_integral range <>) of Boolean;
>    for  seive'component_size use 8;
>    pragma pack(seive);

Send that to the Dept. of Redundancy Department.

The Pack has (and can have) no effect, so there is no reason to give it.
That was one of the points of contention: if the pragma can have no effect
because of some other reason (by-reference types, atomic types, other rep.
clauses), some of us thought it should be rejected (it seems to promise
something it can't deliver - just ignoring it seems harmful).

My preference is to avoid Pack altogether. (We probably took that too far
with Janus/Ada: we never even implemented it. ;-)

                               Randy.