220 36350 <80bbb75a-2a62-537a-3733-898225325a41@technion.ac.il> article Path: news.gmane.org!.POSTED!not-for-mail From: Eyal Rozenberg Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Re: Sub-objects and their copy ellision Date: Tue, 26 Dec 2017 10:05:43 +0100 Lines: 30 Approved: news@gmane.org Message-ID: <80bbb75a-2a62-537a-3733-898225325a41@technion.ac.il> References: <1c6eff77-d71f-4dd7-8c13-f609460a03f0@isocpp.org> <3ec0bd22-b228-4026-bb49-aec5102918c7@isocpp.org> <924751e5-c880-42aa-95ab-99ef1050be2e@isocpp.org> 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 1514279033 1469 195.159.176.226 (26 Dec 2017 09:03:53 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Tue, 26 Dec 2017 09:03:53 +0000 (UTC) User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:57.0) Gecko/20100101 Thunderbird/57.0 To: std-proposals@isocpp.org Original-X-From: std-proposals+bncBDHKZN7LR4ARB3NBRDJAKGQEQVCVBHY@isocpp.org Tue Dec 26 10:03:49 2017 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-wr0-f200.google.com ([209.85.128.200]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1eTl9I-0008Pa-Gx for gclcip-std-proposals@m.gmane.org; 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[192.16.191.27]) by mx.google.com with ESMTPS id q28si829239edb.504.2017.12.26.01.05.49 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 26 Dec 2017 01:05:49 -0800 (PST) Received-SPF: pass (google.com: domain of srs0=uhtng=dw=technion.ac.il=eyalroz@cwi.nl designates 192.16.191.27 as permitted sender) client-ip=192.16.191.27; Original-Received: from fester.cwi.nl (fester.cwi.nl [192.16.191.27]) by fester.cwi.nl (8.14.4/8.12.3) with ESMTP id vBQ95nnR032467 for ; Tue, 26 Dec 2017 10:05:49 +0100 Original-Received: from [192.168.2.1] (ip565d4370.direct-adsl.nl [86.93.67.112] (may be forged)) (authenticated bits=0) by fester.cwi.nl (8.14.4/8.12.3) with ESMTP id vBQ95moB032417 (version=TLSv1/SSLv3 cipher=AES128-SHA bits=128 verify=NO) for ; Tue, 26 Dec 2017 10:05:49 +0100 Openpgp: preference=signencrypt In-Reply-To: <924751e5-c880-42aa-95ab-99ef1050be2e@isocpp.org> Content-Language: en-US X-Original-Sender: eyalroz@technion.ac.il X-Original-Authentication-Results: mx.google.com; spf=pass (google.com: domain of srs0=uhtng=dw=technion.ac.il=eyalroz@cwi.nl designates 192.16.191.27 as permitted sender) smtp.mailfrom=SRS0=UhTng=DW=technion.ac.il=eyalroz@cwi.nl; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=technion.ac.il 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:36350 Archived-At: On 12/25/17 8:15 PM, Nicol Bolas wrote: > On Monday, December 25, 2017 at 1:12:19 PM UTC-5, Antony Polukhin wrote: > > OK, so now we've added a fourth requirement: the function must be > inlinable. Not declared `inline` or something that can be checked by > actual C++ syntax, but some nebulous "inlineable". The second "requirement" was not actually a requirement - and that's due to the potential for inlining, as Antony has explained. If a function call is avoided by inlining, then the compiler may figure out it the caller+callee actually don't need the specific structuring of the arguments to the callee. > Why is this circumstance important enough to be /worth/ all of this hassle? Because right now compilers are entirely-or-partially prevented from applying a useful optimization in some relatively-common cases. > Then why take the time to change the standard to allow it? Because now it (seems to) prevent it, and definitely doesn't encourage it. -- You received this message because you are subscribed to the Google Groups "ISO C++ Standard - Future Proposals" group. 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