From mboxrd@z Thu Jan  1 00:00:00 1970
X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me
X-Spam-Level: 
X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00 autolearn=ham
	autolearn_force=no version=3.4.4
X-Google-Thread: 103376,69431b06fe9a3239
X-Google-NewGroupId: yes
X-Google-Attributes: gida07f3367d7,domainid0,public,usenet
X-Google-Language: ENGLISH,ASCII-7-bit
Path: 
 g2news2.google.com!news4.google.com!feeder.news-service.com!feeder.erje.net!eternal-september.org!feeder.eternal-september.org!.POSTED!not-for-mail
From: Ludovic Brenta <ludovic@ludovic-brenta.org>
Newsgroups: comp.lang.ada
Subject: Re: How do I disable elaboration code on this
Date: Sat, 09 Apr 2011 19:44:40 +0200
Organization: A noiseless patient Spider
Message-ID: <87ipunqpyv.fsf@ludovic-brenta.org>
References: 
 <58bc4fb4-5f6a-48d6-9c98-0dde7ac619df@p16g2000vbo.googlegroups.com>
	<inq539$3tn$1@tornado.tornevall.net> <m2sjtrtl39.fsf@pushface.org>
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Injection-Info: mx02.eternal-september.org;
 posting-host="RdEkHrOTG4z9dP2owN6TLg";
	logging-data="4647"; mail-complaints-to="abuse@eternal-september.org";
	posting-account="U2FsdGVkX19pje2SAhpCXKY9Asi0EM6S"
User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/23.2 (gnu/linux)
Cancel-Lock: sha1:ChDPBY7LiXVbOgPk+yz1pxlnpG8=
	sha1:2ZY6rIOffnBQ0oLSrWF5YGe0Xr8=
Xref: g2news2.google.com comp.lang.ada:19702
Date: 2011-04-09T19:44:40+02:00
List-Id: <comp.lang.ada>

Simon Wright <simon@pushface.org> writes on comp.lang.ada:
> Jeffrey Carter <spam.jrcarter.not@spam.not.acm.org> writes:
>
>> On 04/09/2011 06:58 AM, Lucretia wrote:
>>> The following code will not compile no matter what I do. Basically, I
>>> want to write the startup code for Cortex-M3 in Ada with no assembly.
>>> So, the ISR code needs to be elaboration free as it's the first bit of
>>> code that would run on reset.
>>
>>>     Vector : constant Vectors :=
>>>       (Dummy'Access,
>>>        Dummy'Access,
>>>        Dummy'Access,
>>>        Dummy'Access);
>>>     pragma Convention (C, Vector);
>>>     for Vector'Address use Addr;
>>
>> I think what you need here is
>>
>> Vector : constant Vectors;
>> pragma Import (Ada, Vector);
>> for Vector'Address use Addr;
>>
>> since you don't want Vector to be initialized.
>>
>> Vector will not be initialized because you have pragma Import for it.
>>
>> Note that you don't need procedure Dummy.
>
> But the real code will have actual ISR procedures. OP is merely sparing
> us the unnecessary detail of the real ISRs.

But the vector being in Flash ROM, the Ada code needs not and indeed may
not initialize it, so I think Jeffrey's reply is correct.  The pragma
Import and the address clause will make the actual vectors (in ROM)
visible to the Ada program.

-- 
Ludovic Brenta.