220 15614 <2233213.JephozMv50@tjmaciei-mobl4> article Path: news.gmane.org!not-for-mail From: Thiago Macieira Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Re: Library support for relaxed constexpr Date: Mon, 12 Jan 2015 19:01:56 -0800 Lines: 47 Approved: news@gmane.org Message-ID: <2233213.JephozMv50@tjmaciei-mobl4> References: <5ccd3d6e-859c-4b66-b61c-317b704647f2@isocpp.org> <14072581.09eDfPqFOs@tjmaciei-mobl4> <9F9D7F25-F862-4358-B074-8F8C87255E2A@gmail.com> Reply-To: std-proposals@isocpp.org NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-Trace: ger.gmane.org 1421118127 7940 80.91.229.3 (13 Jan 2015 03:02:07 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Tue, 13 Jan 2015 03:02:07 +0000 (UTC) To: std-proposals@isocpp.org Original-X-From: std-proposals+bncBCB4TK757YBRBKUV2KSQKGQEJORC6LA@isocpp.org Tue Jan 13 04:02:04 2015 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-ie0-f200.google.com ([209.85.223.200]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1YArk3-0003jy-Mo for gclcip-std-proposals@m.gmane.org; Tue, 13 Jan 2015 04:02:03 +0100 Original-Received: by mail-ie0-f200.google.com with SMTP id rd18sf3094289iec.3 for ; Mon, 12 Jan 2015 19:02:02 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:subject:date:message-id:user-agent :in-reply-to:references:mime-version:content-transfer-encoding :content-type:x-original-sender:x-original-authentication-results :reply-to:precedence:mailing-list:list-id:list-post:list-help :list-archive:list-subscribe:list-unsubscribe; bh=ZZFkWvOEfPjejyHvBihaWvRxBYAPzy6IDNr85iNTpf0=; b=RzBu4pQ63A5nuookqOaUrLuVV4VHJc1KfNWgVXEx3zfz2KEeW1tGQDZ/6oWDtMoNs2 Pz0ZLo4gvDJJPaty7hYX6ikJ5UDvYaD2HXaT6f2WjSWBM1wiC+yEKcZx6QFR9BP/QyVy rs1wnvz8sFVLwT4DDUiacFv0tBLXCxUv3iGXn6BfEWjeN4gUn+xFshjlDlKpvOZiAhbB bRc97oAuaZtaDQhB4M9bgmqWRZD6kuX4xIjYAwY6wxfXoTFMo9VQGWhlWUHkOb5I2CJ4 xFNx8wPRayn37vrdiu0nRD9A88XjHoXdxs3FIvVefGQg3nwS7uHvm+JPda3x1Pri4w5Q PvD X-Gm-Message-State: ALoCoQkBzBjNiUEHS7MdMSDDvkOw3UUiay2zszTxztk48S841G13EA4DbzZhSxMJhb8KjNnGKLAK X-Received: by 10.182.200.133 with SMTP id js5mr13117120obc.29.1421118122701; Mon, 12 Jan 2015 19:02:02 -0800 (PST) X-BeenThere: std-proposals@isocpp.org Original-Received: by 10.50.112.2 with SMTP id im2ls908770igb.15.canary; Mon, 12 Jan 2015 19:02:01 -0800 (PST) X-Received: by 10.107.40.16 with SMTP id o16mr31623437ioo.26.1421118121891; Mon, 12 Jan 2015 19:02:01 -0800 (PST) Original-Received: from gondolin.macieira.info (gondolin.macieira.info. [2a01:4f8:d13:f81:21c:14ff:fe01:12a3]) by mx.google.com with ESMTP id vf12si3226374igb.8.2015.01.12.19.02.01 for ; Mon, 12 Jan 2015 19:02:01 -0800 (PST) Received-SPF: pass (google.com: domain of thiago@macieira.org designates 2a01:4f8:d13:f81:21c:14ff:fe01:12a3 as permitted sender) client-ip=2a01:4f8:d13:f81:21c:14ff:fe01:12a3; Original-Received: from tjmaciei-mobl4.localnet (unknown [IPv6:2601:7:1c82:413a:5e51:4fff:fe7c:49f8]) by gondolin.macieira.info (Postfix) with ESMTPSA id ED0D711A73E for ; Mon, 12 Jan 2015 19:01:59 -0800 (PST) User-Agent: KMail/4.14.3 (Linux/3.11.10-21-desktop; KDE/4.14.3; x86_64; ; ) In-Reply-To: <9F9D7F25-F862-4358-B074-8F8C87255E2A@gmail.com> X-Original-Sender: thiago@macieira.org X-Original-Authentication-Results: mx.google.com; spf=pass (google.com: domain of thiago@macieira.org designates 2a01:4f8:d13:f81:21c:14ff:fe01:12a3 as permitted sender) smtp.mail=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:15614 Archived-At: On Tuesday 13 January 2015 09:18:13 David Krauss wrote: > > On 2015=E2=80=9301=E2=80=9313, at 6:43 AM, Thiago Macieira wrote: > >=20 > > Note that the difference is whether the intrinsic functions are conside= red >=20 > > constexpr or not. For GCC, __builtin_ldexp is constexpr but isn't for= =20 Clang: > For GCC, most of is constexpr because it has supported compile-ti= me > evaluation of constant floating-point expressions since time immemorial. > Only in C++11 (once constexpr extensions were forbidden) did this extensi= on > become nonconforming. >=20 > I almost finished a paper for Urbana, =E2=80=9CRefining floating-point co= nstexpr,=E2=80=9D > but ultimately I had enough other material, and the implementations kept > evolving under my feet. I should finish it and find a presenter for Lenex= a. > Co-authors are welcome! I believe you should leave those functions in cmath be optionally constexpr= ..=20 Compilers do not have to make them constexpr if they are not equipped for= =20 evaluating them at compile time, like GCC was. --=20 Thiago Macieira - thiago (AT) macieira.info - thiago (AT) kde.org Software Architect - Intel Open Source Technology Center PGP/GPG: 0x6EF45358; fingerprint: E067 918B B660 DBD1 105C 966C 33F5 F005 6EF4 5358 --=20 ---=20 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 e= mail to std-proposals+unsubscribe@isocpp.org. To post to this group, send email to std-proposals@isocpp.org. Visit this group at http://groups.google.com/a/isocpp.org/group/std-proposa= ls/. .