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=-1.3 required=5.0 tests=BAYES_00,INVALID_MSGID autolearn=no autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,ffdd4d59cbfb4caf X-Google-Attributes: gid103376,public From: bobduff@world.std.com (Robert A Duff) Subject: Re: Ada 95 Numerics questions for the experts Date: 1997/09/08 Message-ID: #1/1 X-Deja-AN: 270789869 References: Organization: The World Public Access UNIX, Brookline, MA Newsgroups: comp.lang.ada Date: 1997-09-08T00:00:00+00:00 List-Id: I said: ><size of the components (e.g. because you're interfacing to external >hardware or software), then use a Component_Size clause. If you just >want to squeeze the thing down to a reasonably small size, because you >know that will be more efficient, then pragma Pack is more appropriate. In article , Robert Dewar wrote: >This is surpringly wrong. Bob, you must go read the RM, it was written >by this clever fellow Bob Duff, and will tell you the TRUTH :-) :-) Sorry, I should have clarified that my advice was stylistic. It doesn't matter what the RM says -- stylistically, Pack means "minimize space, more or less", and "for T'Component_Size use N" means, "I want exactly N-bit components". Surely Pack had that feeling in Ada 83, and the addition of requirements in Ada 95 was merely a response to implementations that failed to do *anything* to minimize space, so we had to specify *how much* (as a minimum) space has to be minimized. Besides, the allegedly "clever" Bob Duff who wrote that portion of the RM is no more. I no longer spend 24-hours a day thinking about language issues. ;-) >First, in the absence of implementation of annex C, neither declaration >will guarantee close packing. Yeah, yeah, I know that all bets are off if the impl doesn't support Annex C. - Bob