220 36473 <2503165.NFYEXWA1nm@tjmaciei-mobl1> article Path: news.gmane.org!.POSTED!not-for-mail From: Thiago Macieira Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Re: Treating local variables as rvalues in return statements Date: Wed, 03 Jan 2018 11:50:01 -0200 Lines: 37 Approved: news@gmane.org Message-ID: <2503165.NFYEXWA1nm@tjmaciei-mobl1> References: <4ff5fe2d-0945-491f-9888-479b8e866ace@isocpp.org> <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 1514987288 11451 195.159.176.226 (3 Jan 2018 13:48:08 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Wed, 3 Jan 2018 13:48:08 +0000 (UTC) To: std-proposals@isocpp.org Original-X-From: std-proposals+bncBCB4TK757YBRBDF7WPJAKGQELPKVSJY@isocpp.org Wed Jan 03 14:48:03 2018 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-qk0-f200.google.com ([209.85.220.200]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1eWjOk-0002ek-8Y for gclcip-std-proposals@m.gmane.org; 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[209.222.10.136]) by mx.google.com with ESMTPS id 29si806446qtm.229.2018.01.03.05.50.04 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 03 Jan 2018 05:50:04 -0800 (PST) Received-SPF: pass (google.com: domain of thiago@macieira.org designates 209.222.10.136 as permitted sender) client-ip=209.222.10.136; Original-Received: from tjmaciei-mobl1.localnet (unknown [191.254.125.70]) by smtp.macieira.info (Postfix) with ESMTPSA id 87755587D for ; Wed, 3 Jan 2018 05:50:03 -0800 (PST) In-Reply-To: X-Original-Sender: thiago@macieira.org X-Original-Authentication-Results: mx.google.com; spf=pass (google.com: domain of thiago@macieira.org designates 209.222.10.136 as permitted sender) smtp.mailfrom=thiago@macieira.org 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:36473 Archived-At: On Wednesday, 3 January 2018 11:39:51 -02 Olaf van der Spek wrote: > 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). Because I have the suspicion that it can't exist at all. The idea is bad if it can't be described meaningfully. -- Thiago Macieira - thiago (AT) macieira.info - thiago (AT) kde.org Software Architect - Intel Open Source Technology Center -- 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/2503165.NFYEXWA1nm%40tjmaciei-mobl1. .