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=unavailable autolearn_force=no version=3.4.4 Path: eternal-september.org!reader01.eternal-september.org!reader02.eternal-september.org!news.eternal-september.org!news.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail From: Simon Clubley Newsgroups: comp.lang.ada Subject: Re: Forcing GNAT to use 32-bit load/store instructions on ARM? Date: Tue, 8 Jul 2014 12:12:22 +0000 (UTC) Organization: A noiseless patient Spider Message-ID: References: <0e0b9ac2-e793-4cc5-8d8d-d3441ca28a58@googlegroups.com> <1j7b0m3yptffy$.1cztnkty8elrv$.dlg@40tude.net> Injection-Date: Tue, 8 Jul 2014 12:12:22 +0000 (UTC) Injection-Info: mx05.eternal-september.org; posting-host="e458ff8b81bc0c159989eb0e36c6e372"; logging-data="30961"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX18/PzPMYODkZnFqunx0M1Xzjdrm+AQpTBg=" User-Agent: slrn/0.9.8.1 (VMS/Multinet) Cancel-Lock: sha1:Cw9RtD8DcbjV8/2dqbKQUfncCaU= Xref: news.eternal-september.org comp.lang.ada:20798 Date: 2014-07-08T12:12:22+00:00 List-Id: On 2014-07-07, Randy Brukardt wrote: > > Clearly, we need a partial aggregate syntax (it's the only way for an atomic > record write to make sense), and that needs to be clear that it includes > both a read and a write of the object for the purposes of volatile > variables. Probably someone should submit this problem to Ada-Comment for > study in the next version of Ada (whenever that might be). > What are the submission details for Ada-Comment ? (Searching for Ada Comments just points to links about using comments in Ada code.) What is the level of formality and problem detail required in the submission ? I also wonder if "Atomic" is the correct word here; perhaps something like "Non_Segmented_Access" would be a better attribute name when we _must_ access the register in units of the record size and don't really care about the Read-Modify-Write sequence itself being indivisible. _We_ "know" that Atomic in this case really only means there's a single, full-sized read and a single full-sized write of the register and that the whole Read-Modify-Write sequence itself isn't really indivisible. However, it's reasonable for a newcomer to Ada to wonder if Atomic really does mean the whole Read-Modify-Write sequence itself is indivisible. One of the goals of Ada is to express clarity when writing code and "Non_Segmented_Access" expresses the intent here better than Atomic does. Simon. -- Simon Clubley, clubley@remove_me.eisner.decus.org-Earth.UFP Microsoft: Bringing you 1980s technology to a 21st century world