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,ae395e5c11de7bc9
X-Google-NewGroupId: yes
X-Google-Attributes: gida07f3367d7,domainid0,public,usenet
X-Google-Language: ENGLISH,ASCII
Path: 
 g2news2.google.com!postnews.google.com!b9g2000pri.googlegroups.com!not-for-mail
From: Jerry <lanceboyle@qwest.net>
Newsgroups: comp.lang.ada
Subject: Re: segfault with large-ish array with GNAT
Date: Fri, 19 Mar 2010 16:24:41 -0700 (PDT)
Organization: http://groups.google.com
Message-ID: <58da0e59-418b-4545-a29c-9403d1ab6288@b9g2000pri.googlegroups.com>
References: 
 <642ddf8b-1d45-4f74-83ad-2c755040ca33@k24g2000pro.googlegroups.com>
	<cf178987-c893-4e93-83b7-c86b6aeeac48@q15g2000yqj.googlegroups.com>
	<4ba13454$0$6720$9b4e6d93@newsspool2.arcor-online.net>
 <ac4bed10-f655-4fa5-8891-2967ba4388a0@k6g2000prg.googlegroups.com>
	<12q6q5hjqihq8lpgpt9mjmn30l9q9lrmkm@4ax.com>
 <ho0mqe$efe$1@tornado.tornevall.net>
NNTP-Posting-Host: 75.172.190.146
Mime-Version: 1.0
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: quoted-printable
X-Trace: posting.google.com 1269041081 7403 127.0.0.1 (19 Mar 2010 23:24:41
 GMT)
X-Complaints-To: groups-abuse@google.com
NNTP-Posting-Date: Fri, 19 Mar 2010 23:24:41 +0000 (UTC)
Complaints-To: groups-abuse@google.com
Injection-Info: b9g2000pri.googlegroups.com; posting-host=75.172.190.146;
	posting-account=x5rpZwoAAABMN2XPwcebPWPkebpwQNJG
User-Agent: G2/1.0
X-HTTP-UserAgent: Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10_5_8; en-US)
	AppleWebKit/528.16+(KHTML, like Gecko,
 Safari/528.16) OmniWeb/v622.8.0,gzip(gfe),gzip(gfe)
Xref: g2news2.google.com comp.lang.ada:10648
Date: 2010-03-19T16:24:41-07:00
List-Id: <comp.lang.ada>

On Mar 19, 1:22=A0pm, "Jeffrey R. Carter"
<spam.jrcarter....@spam.acm.org> wrote:
> Brian Drummond wrote:
>
> > But code using the array can be written as normal, with a "my_array ...=
 renames
> > my_array_ptr.all" clause to hide the pointer.
>
> Generally, after something like
>
> A : constant Array_Ptr :=3D new Array_Type [(Low .. High)];
>
> You can use A just as if it were the array itself:
>
> B :=3D A (A'First);
> A (A'First) :=3D A (A'Last);
> A (A'Last) :=3D B;
>
> --
> Jeff Carter

That is true when accessing array elements and slices but not for
indicating the entire array as a single entity such as in a subroutine
argument, e.g.

y :=3D cos(x);

or

z :=3D x + y;

with

function "+"   (Left, Right : Real_Vector) return Real_Vector;

which is from ARM G.3.1.

Using access variables without renaming, the above line would have to
be written

y :=3D cos(x.all);

and

z.all :=3D x.all + y.all;

and in the algebraic-like calculations that are possible using
overloads the .all's clutter up the equation a bit. It's just a matter
of where you want to put the eye pollution. I have an extensive
library of subroutines including overloads that work with Real_Vector
and Complex_Vector from G.3 and either way (renaming or .all-ing)
works fine but on balance I think renaming is easier to read (and
probably easier to forget to release memory 8^( .)

Jerry