220 36471 <3356554.N1GgDjyayG@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 11:31:26 -0200 Lines: 27 Approved: news@gmane.org Message-ID: <3356554.N1GgDjyayG@tjmaciei-mobl1> References: <4ff5fe2d-0945-491f-9888-479b8e866ace@isocpp.org> <1823126.nxGvHgdJMA@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 1514986231 26853 195.159.176.226 (3 Jan 2018 13:30:31 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Wed, 3 Jan 2018 13:30:31 +0000 (UTC) To: std-proposals@isocpp.org Original-X-From: std-proposals+bncBCB4TK757YBRB25WWPJAKGQEPRCO43I@isocpp.org Wed Jan 03 14:30:27 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 1eWj7h-0006ax-5m for gclcip-std-proposals@m.gmane.org; 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[2001:19f0:5:2221::1:3]) by mx.google.com with ESMTPS id g42si767794qta.431.2018.01.03.05.32.26 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 03 Jan 2018 05:32:26 -0800 (PST) Received-SPF: pass (google.com: domain of thiago@macieira.org designates 2001:19f0:5:2221::1:3 as permitted sender) client-ip=2001:19f0:5:2221::1:3; Original-Received: from tjmaciei-mobl1.localnet (unknown [191.254.125.70]) by smtp.macieira.info (Postfix) with ESMTPSA id 8EDF35873 for ; Wed, 3 Jan 2018 05:31:33 -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 2001:19f0:5:2221::1:3 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:36471 Archived-At: 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. -- 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/3356554.N1GgDjyayG%40tjmaciei-mobl1. .