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Newsgroups: comp.lang.ada
Date: Mon, 7 Sep 2015 04:54:03 -0700 (PDT)
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Subject: Re: Addressing in Object Ada v/s GNAT (2013)  showing Vast
 Differences
From: Lucas Redding <lucas.redding@gmail.com>
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Xref: news.eternal-september.org comp.lang.ada:27726
Date: 2015-09-07T04:54:03-07:00
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On Monday, September 7, 2015 at 12:39:35 PM UTC+1, Lucas Redding wrote:
> Hi
>=20
> I was wondering how the addressing mechanism works in GNAT Ada? Is it so =
vastly different to Object Ada? Is there a way I can tailor the GNAT addres=
sing mechanism to follow that of Object Ada?
>=20
> I have a program that runs perfectly in Object Ada. The program relies he=
avily on "USE AT" clauses together with 'SIZE on underlying type definition=
. This is in order to map directly and deterministically to memory with bit=
 precision. The data is independently produced so this is very important.
>=20
> I have compiled the program is GNAT Ada but I am getting run time errors =
such as "misaligned address value". More worryingly, any data read from mem=
ory that relies on the addressing mechanisms described above is incoherent.
>=20
> I am interested in moving to GNAT Ada because I believe the accompanying =
toolset is much richer and therefore more productive but I am beginning to =
wonder whether this is too onerous task?
>=20
> Any help is greatly appreciated.
>=20
> Lucas

Hi,=20

I forgot to say that platform is Windows 7 (64 bit if that matters) and the=
 data is in S_RECORD format (With correct ENDIANISM).

Any help is greatly appreciated.

Lucas