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From: Adam Beneschan <adam@irvine.com>
Newsgroups: comp.lang.ada
Subject: Re: pragma Pack vs. Convention C, portability issue?
Date: Fri, 11 Jan 2008 16:35:15 -0800 (PST)
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On Jan 11, 11:53 am, "(see below)" <yaldni...@blueyonder.co.uk> wrote:
> On 11/1/08 04:20, in article fm8e95$q0...@jacob-sparre.dk,
>
> "Randy Brukardt" <ra...@rrsoftware.com> wrote:
>
> > Moral: avoid Pack for anything where the representation matters to
> > portability. Use 'Component_Size instead.
>
> 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);
>
> or even this:
>
>    type a_set is array (a_member) of Boolean;
>    for  a_set'Component_Size use 1;
>    pragma Pack(a_set);
>    pragma Convention(C, Entity => a_set);

13.2(9) makes me think that the 'Component_Size clause is honored and
the Pack pragma can't change it.

                                 -- Adam