220 35049 <1627526.sOtCnR7rdP@tjmaciei-mobl1> article Path: news.gmane.org!.POSTED!not-for-mail From: Thiago Macieira Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Re: standard attribute for unions to pun types? 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mx.google.com; spf=pass (google.com: domain of thiago@macieira.org designates 78.47.120.188 as permitted sender) smtp.mailfrom=thiago@macieira.org Original-Received: from gondolin.macieira.info (gondolin.macieira.info. [78.47.120.188]) by mx.google.com with ESMTP id b128si1108546wmg.60.2017.10.20.09.24.40 for ; Fri, 20 Oct 2017 09:24:40 -0700 (PDT) Received-SPF: pass (google.com: domain of thiago@macieira.org designates 78.47.120.188 as permitted sender) client-ip=78.47.120.188; Original-Received: from tjmaciei-mobl1.localnet (unknown [12.130.127.32]) by gondolin.macieira.info (Postfix) with ESMTPSA id C440211B4F8 for ; Fri, 20 Oct 2017 09:24:39 -0700 (PDT) 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 78.47.120.188 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-Google-Group-Id: 399137483710 List-Post: , List-Help: , List-Archive: List-Subscribe: , List-Unsubscribe: , Xref: news.gmane.org gmane.comp.lang.c++.isocpp.proposals:35049 Archived-At: On Friday, 20 October 2017 07:23:11 PDT Hyman Rosen wrote: > On Fri, Oct 20, 2017 at 5:01 AM, Bo Persson wrote: > > If you check the code generated by the popular compilers, you will see > > that `bit_cast` doesn't really copy anything (despite containing a > > memcpy). > > > > Returning a value is optimized into a register load from the source. > > That's it. > > Nevertheless, if I want to, say, set a float to its next representable > value, I want to do No, you want to do: float_val = std::nextafter(float_val, std::numeric_limits::infinity()); -- 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. 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