220 36470 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 13:32:40 +0100 Lines: 22 Approved: news@gmane.org Message-ID: References: <4ff5fe2d-0945-491f-9888-479b8e866ace@isocpp.org> <55bb7162-834a-4ba4-bd68-915470842430@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 1514982646 20222 195.159.176.226 (3 Jan 2018 12:30:46 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Wed, 3 Jan 2018 12:30:46 +0000 (UTC) To: "ISO C++ Standard - Future Proposals" Original-X-From: std-proposals+bncBC5NB45SSABBB2U2WPJAKGQEO7U2N3Y@isocpp.org Wed Jan 03 13:30:42 2018 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-oi0-f71.google.com ([209.85.218.71]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1eWiBr-0004lD-Oe for gclcip-std-proposals@m.gmane.org; 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[209.85.220.41]) by mx.google.com with SMTPS id m18sor295666otb.260.2018.01.03.04.32.42 for (Google Transport Security); Wed, 03 Jan 2018 04:32:42 -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 10.157.31.61 with SMTP id x58mr708097otd.85.1514982761694; Wed, 03 Jan 2018 04:32:41 -0800 (PST) Original-Received: by 10.157.55.163 with HTTP; Wed, 3 Jan 2018 04:32:40 -0800 (PST) In-Reply-To: <1823126.nxGvHgdJMA@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=D3+8yonm; 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:36470 Archived-At: 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. -- 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/CAA7U3HPMh9VHo_16djyzT0KnzVf%2Bab0Nm2CoU7zFfKJqCyfJ3w%40mail.gmail.com. .