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From: Stephen Leake <stephen.a.leake.1@gsfc.nasa.gov>
Newsgroups: comp.lang.ada
Subject: Re: Import a type from C
Date: 07 Nov 2002 08:47:54 -0500
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porton@ex-code.com (Victor Porton) writes:

> May be specifying both
> 
> pragma Convention( C, My_Data );
> and
> pragma Pack( My_Type );
> 
> will be compatible with gcc -fpacked?

Well, it might, but the standard doesn't say. Actually, I would hope
the compiler would reject this, since it is asking for conflicting
things. 

I guess my real point is that the standard does _not_ clearly state
what Convention (C, ...) really means (it is entirely implementation
dependent), so I can't rely on it.

Ada is supposed to be easy to _read_, not necessarily easy to _write_.
Convention (C) is just a shortcut for the proper rep clause.

Hmm. I guess if you have two Ada compilers, and two corresponding C
compilers, and you use the correct command line flags on the C
compilers, and the corresponding rep clauses are different, then
Convention C is a better alternative than gnatprep to choose the
representation. However, in my experience, I end up needing gnatprep
(for other reasons) in a situation like that anyway.

-- 
-- Stephe