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From: Robert Dewar <robert_dewar@my-deja.com>
Subject: Re: generic package dilemma
Date: 1999/12/04
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In article <828nuu$95s$1@nnrp1.deja.com>,
  Ted Dennison <dennison@telepath.com> wrote:

> Interesting. Have you given any thought to doing this for
> other implemetation-defined things, like ordering of record
> fields and caching of global data?

No, because that does not serve the purpose of writing reliable
programs using GNAT. In the case of elaboration order, if you
are using -gnatE, you really want to make sure that all the
necessary pragma Elaborate_All statements are in place, since
otherwise your program can run into maintenance problems when
changes are made.

However, in the case of ordering of record fields, we guarantee
that there is no reordering in GNAT, so that is not a source
of unreliability. It might be useful if you are using GNAT to
develop programs that are intended to port to other Ada
compilers, but our primary goal is to provide the features to
write reliable programs using GNAT, so this is definitely a
secondary low priority goal.

We do give warnings in cases where the code has clearly
undesirable implementation dependent properties that might
change in future releases.


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