220 36472 article Path: news.gmane.org!.POSTED!not-for-mail From: Olaf van der Spek Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Re: Treating local variables as rvalues in return statements Date: Wed, 3 Jan 2018 14:39:51 +0100 Lines: 34 Approved: news@gmane.org Message-ID: References: <4ff5fe2d-0945-491f-9888-479b8e866ace@isocpp.org> <1823126.nxGvHgdJMA@tjmaciei-mobl1> <3356554.N1GgDjyayG@tjmaciei-mobl1> Reply-To: std-proposals@isocpp.org NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" X-Trace: blaine.gmane.org 1514986683 3378 195.159.176.226 (3 Jan 2018 13:38:03 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Wed, 3 Jan 2018 13:38:03 +0000 (UTC) To: "ISO C++ Standard - Future Proposals" Original-X-From: std-proposals+bncBC5NB45SSABBBKV2WPJAKGQEMUEEEKI@isocpp.org Wed Jan 03 14:37:59 2018 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-oi0-f70.google.com ([209.85.218.70]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1eWjEu-0008VI-83 for gclcip-std-proposals@m.gmane.org; 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[209.85.220.41]) by mx.google.com with SMTPS id w42sor331019ota.40.2018.01.03.05.39.54 for (Google Transport Security); Wed, 03 Jan 2018 05:39:54 -0800 (PST) Received-SPF: pass (google.com: domain of olafvdspek@gmail.com designates 209.85.220.41 as permitted sender) client-ip=209.85.220.41; X-Received: by 10.157.44.34 with SMTP id f31mr899980otb.193.1514986792944; Wed, 03 Jan 2018 05:39:52 -0800 (PST) Original-Received: by 10.157.55.163 with HTTP; Wed, 3 Jan 2018 05:39:51 -0800 (PST) In-Reply-To: <3356554.N1GgDjyayG@tjmaciei-mobl1> X-Original-Sender: olafvdspek@gmail.com X-Original-Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com header.s=20161025 header.b=ipLAn9pp; spf=pass (google.com: domain of olafvdspek@gmail.com designates 209.85.220.41 as permitted sender) smtp.mailfrom=olafvdspek@gmail.com; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=gmail.com Precedence: list Mailing-list: list std-proposals@isocpp.org; contact std-proposals+owners@isocpp.org List-ID: X-Spam-Checked-In-Group: std-proposals@isocpp.org X-Google-Group-Id: 399137483710 List-Post: , List-Help: , List-Archive: List-Subscribe: , List-Unsubscribe: , Xref: news.gmane.org gmane.comp.lang.c++.isocpp.proposals:36472 Archived-At: 2018-01-03 14:31 GMT+01:00 Thiago Macieira : > On Wednesday, 3 January 2018 10:32:40 -02 Olaf van der Spek wrote: >> 2018-01-03 12:33 GMT+01:00 Thiago Macieira : >> > On Wednesday, 3 January 2018 08:51:05 -02 olafvdspek@gmail.com wrote: >> >> Wouldn't the idea be to do the analysis and only consider it a rvalue if >> >> it's NOT accessed later in the statement / function? >> > >> > And its address has never been taken, which also means it must never have >> > been passed by reference either. That limits the usefulness too much to >> > make it a feature. >> >> Taking the address is fine as long as all references are dead by the >> time it's considered an rvalue. > > And how do you prove that they are? > > Please answer in standardese, not in terms of compiler optimisations. Why? An idea isn't bad just because standardese isn't available (yet). I'm also not saying this is easy to do or worthwhile to focus on BTW. Gr, -- Olaf -- You received this message because you are subscribed to the Google Groups "ISO C++ Standard - Future Proposals" group. To unsubscribe from this group and stop receiving emails from it, send an email to std-proposals+unsubscribe@isocpp.org. To post to this group, send email to std-proposals@isocpp.org. To view this discussion on the web visit https://groups.google.com/a/isocpp.org/d/msgid/std-proposals/CAA7U3HMDj3r5M70izHb30%2Bo1xHqUhgYX2KERBvvvgeAsq--muA%40mail.gmail.com. .