From mboxrd@z Thu Jan  1 00:00:00 1970
X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on
	ip-172-31-65-14.ec2.internal
X-Spam-Level: 
X-Spam-Status: No, score=-1.9 required=3.0 tests=BAYES_00,T_SCC_BODY_TEXT_LINE
	autolearn=ham autolearn_force=no version=3.4.6
Path: eternal-september.org!feeder.eternal-september.org!news.mixmin.net!news2.arglkargh.de!news.karotte.org!fu-berlin.de!uni-berlin.de!individual.net!not-for-mail
From: Niklas Holsti <niklas.holsti@tidorum.invalid>
Newsgroups: comp.lang.ada
Subject: Constancy of X'Address?
Date: Wed, 5 Apr 2023 12:24:39 +0300
Organization: Tidorum Ltd
Message-ID: <k94t2nFelgbU1@mid.individual.net>
Mime-Version: 1.0
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 7bit
X-Trace: individual.net juDKVaBYK50YlczI6SaMHQeKit8sKDr5/XWq9+txS5IGT923Oo
Cancel-Lock: sha1:9BjAnEvFBfxzAKv0hYKrLm8Ga34=
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.14; rv:102.0)
 Gecko/20100101 Thunderbird/102.6.1
Content-Language: en-US
Xref: feeder.eternal-september.org comp.lang.ada:65071
List-Id: <comp.lang.ada>

A discussion in comp.arch (on the new C23 standard for C) brought up 
these questions, which I could not answer with confidence:

- Is the address of an object constant in Ada? That is, if I have some 
object X in an Ada program, do repeated applications of X'Address always 
return the same value?

- Does the answer depend on how X is allocated (created): on the library 
level, on the stack, or in a pool ("new")?

The issue behind this question is whether an Ada program could use 
garbage collection that moves objects around, for example a compacting 
collector.