220 25463 article Path: news.gmane.org!not-for-mail From: Matthew Woehlke Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Relocation as a solution for the valueless variant problem? 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[80.91.229.3]) by mx.google.com with ESMTPS id rs10si1421720lbb.152.2016.04.06.09.16.23 for (version=TLS1 cipher=AES128-SHA bits=128/128); Wed, 06 Apr 2016 09:16:23 -0700 (PDT) Received-SPF: pass (google.com: domain of gclcip-std-proposals@m.gmane.org designates 80.91.229.3 as permitted sender) client-ip=80.91.229.3; Original-Received: from list by plane.gmane.org with local (Exim 4.69) (envelope-from ) id 1anq7w-0003VR-8G for std-proposals@isocpp.org; Wed, 06 Apr 2016 18:16:20 +0200 Original-Received: from tripoint.kitware.com ([66.194.253.20]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Wed, 06 Apr 2016 18:16:20 +0200 Original-Received: from mwoehlke.floss by tripoint.kitware.com with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Wed, 06 Apr 2016 18:16:20 +0200 X-Injected-Via-Gmane: http://gmane.org/ Original-Lines: 17 Original-X-Complaints-To: usenet@ger.gmane.org X-Gmane-NNTP-Posting-Host: tripoint.kitware.com User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.7.0 In-Reply-To: X-Original-Sender: mwoehlke.floss@gmail.com X-Original-Authentication-Results: mx.google.com; spf=pass (google.com: domain of gclcip-std-proposals@m.gmane.org designates 80.91.229.3 as permitted sender) smtp.mailfrom=gclcip-std-proposals@m.gmane.org; dmarc=fail (p=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:25463 Archived-At: On 2016-04-06 12:07, Sean Middleditch wrote: > I personally find this relocation proposal currently incomplete and in > need of a lot more iteration. With your proposal, it's way too easy to > accidentally leave some object in an undefined state where the > compiler has no idea and is stuck calling the destructor anyway. All > it takes is passing an object via pointer to some function and *bam* > insta-pain, as the caller has no way to know what the function will do > and the function has no way to know what the caller wanted to allow, > other than comments and documentation (no compiler support for error > checking). Right now, if I pass a pointer to an object to a function, that function can `delete` the pointer. How does relocation make this any worse? In both cases, the pointer passed in is no longer valid. -- Matthew -- 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/ne3cod%24a8n%241%40ger.gmane.org. .