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,FREEMAIL_FROM autolearn=unavailable autolearn_force=no version=3.4.4 X-Received: by 10.107.6.37 with SMTP id 37mr5530672iog.73.1494732287235; Sat, 13 May 2017 20:24:47 -0700 (PDT) X-Received: by 10.157.45.79 with SMTP id v73mr222373ota.20.1494732287210; Sat, 13 May 2017 20:24:47 -0700 (PDT) Path: eternal-september.org!reader01.eternal-september.org!reader02.eternal-september.org!news.eternal-september.org!news.eternal-september.org!feeder.eternal-september.org!news.glorb.com!c26no1328635itd.0!news-out.google.com!v18ni1753ita.0!nntp.google.com!c26no1328631itd.0!postnews.google.com!glegroupsg2000goo.googlegroups.com!not-for-mail Newsgroups: comp.lang.ada Date: Sat, 13 May 2017 20:24:46 -0700 (PDT) In-Reply-To: Complaints-To: groups-abuse@google.com Injection-Info: glegroupsg2000goo.googlegroups.com; posting-host=2601:191:8303:2100:5985:2c17:9409:aa9c; posting-account=fdRd8woAAADTIlxCu9FgvDrUK4wPzvy3 NNTP-Posting-Host: 2601:191:8303:2100:5985:2c17:9409:aa9c References: User-Agent: G2/1.0 MIME-Version: 1.0 Message-ID: Subject: Re: Rust's temporal safety for Ada/SPARK From: Robert Eachus Injection-Date: Sun, 14 May 2017 03:24:47 +0000 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Xref: news.eternal-september.org comp.lang.ada:46775 Date: 2017-05-13T20:24:46-07:00 List-Id: I'm going to try to avoid getting into a long discussion here. The part of= Rust referenced is similar to Ada without tasking. As Jeffery Carter point= s out, most of the time Ada scope rules deal with this at compile time. Th= ere are some cases that require run-time checking, and most programmers con= sider code that needs run-time checking as a bug. (In SPARK, it is. ;-) As for concurrency of the type we have been discussing in another thread, i= t is at a very low level, and should usually only come up in hard real-time= code. If you have time limits in milliseconds or less, just using the Ada= thread safe versions of data structures are not well defined enough. What= we are/were discussing was code that is lock free, and where synchronizati= on will cause one CPU core to stall (usually for just much less than a micr= osecond.) until the data is available, rather than a sleep-state or task sw= itch.