220 37346 <08d4fa62-ab7d-f257-5a50-fc77f4d35a24@gmail.com> article
Path: news.gmane.org!.POSTED!not-for-mail
From: Andrey Semashev <andrey.semashev@gmail.com>
Newsgroups: gmane.comp.lang.c++.isocpp.proposals
Subject: Re: `offsetof` in a macro-less, modular world
Date: Thu, 15 Mar 2018 23:53:54 +0300
Lines: 16
Approved: news@gmane.org
Message-ID: <08d4fa62-ab7d-f257-5a50-fc77f4d35a24@gmail.com>
References: <c5f5ccc4-3267-442d-8cb2-de1ae103a38e@isocpp.org>
 <CALmDwq38-kBPK2QnEPLkzM9z7r_jXif7oBoO+A7CMm9XBUC96g@mail.gmail.com>
 <8745898.m7JMjNCkYK@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"; format=flowed
X-Trace: blaine.gmane.org 1521147116 17972 195.159.176.226 (15 Mar 2018 20:51:56 GMT)
X-Complaints-To: usenet@blaine.gmane.org
NNTP-Posting-Date: Thu, 15 Mar 2018 20:51:56 +0000 (UTC)
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101
 Thunderbird/52.6.0
To: std-proposals@isocpp.org
Original-X-From: std-proposals+bncBCXY5TXHWYJRBZN2VPKQKGQEMYON4VQ@isocpp.org Thu Mar 15 21:51:52 2018
Return-path: <std-proposals+bncBCXY5TXHWYJRBZN2VPKQKGQEMYON4VQ@isocpp.org>
Envelope-to: gclcip-std-proposals@m.gmane.org
Original-Received: from mail-lf0-f69.google.com ([209.85.215.69])
	by blaine.gmane.org with esmtp (Exim 4.84_2)
	(envelope-from <std-proposals+bncBCXY5TXHWYJRBZN2VPKQKGQEMYON4VQ@isocpp.org>)
	id 1ewZqp-0004af-Mx
	for gclcip-std-proposals@m.gmane.org; Thu, 15 Mar 2018 21:51:51 +0100
Original-Received: by mail-lf0-f69.google.com with SMTP id p87-v6sf2709603lfg.8
        for <gclcip-std-proposals@m.gmane.org>; Thu, 15 Mar 2018 13:53:58 -0700 (PDT)
ARC-Seal: i=2; a=rsa-sha256; t=1521147238; cv=pass;
        d=google.com; s=arc-20160816;
        b=HWlMFQMSNdj2RXbQWUWZmllKDfiLI7gO9pSUBdIDsbuu/oEyXAURRry+v+wDedIazI
         I4U3uKmPF6CyUxxm8NAtJCs2AdY6mtmcQhiipz3UqBazkk6u2CTsiswySvuVfo2kOC4w
         yUuwCXf8A34qmiJdJIHECHNRdRX9bw1AnOlxNpmuYVaNDZYizhgcMXxXyqMUgDXIEJLt
         OrEkjQ4gDTP6rLeynwTcLQ2syVy0KhmDE4Hj97V759r7s7zNkWs2Achem/sf1XiU+WJJ
         cXmo9pAEUXqQYneJ88ov9L5HJldn2oW8qGVW1huWHX+BpvaQcX1/RX80plGeQkiyhQ9k
         xy8g==
ARC-Message-Signature: i=2; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816;
        h=list-unsubscribe:list-subscribe:list-archive:list-help:list-post
         :list-id:mailing-list:precedence:reply-to:content-language
         :in-reply-to:mime-version:user-agent:date:message-id:from:references
         :to:subject:arc-authentication-results:arc-message-signature
         :dkim-signature:arc-authentication-results;
        bh=gC5vu6c9IPIBwzHCGwgcZt8+PUEAnV62gHAdvVJYcSA=;
        b=VRWvz4sQ5zv+KMFHv5IpPHmpbUIetJven0lAIrWg2oJfA/iC2xkD07lld9EvvjL5Av
         uVpifprtSCtT/JkkTp+TmooZDSXkvN1KHsCWh9T/SNA4RQdAGsFEF3+kDJOVUxkwLcZd
         BiOHMmoxJ5g77PeYTKvsPUlwXscdWcpwM6cRK8XBG3fp51sZuJbkE6q/r2aBZPThPcGS
         4ssVUgna9DDVnFkZ/2RAiCazgbuDut/7x8hRjl9IqMFcTgAfUAs1xc8wFpu2j6op+KoS
         /pO2ioI9sM2CIOcUFhAZnXJZMzlu6lQXP5uenff19pFqAYvv5BvJyqQnpcAuYjxayO2s
         FWVw==
ARC-Authentication-Results: i=2; mx.google.com;
       dkim=pass header.i=@gmail.com header.s=20161025 header.b=Hu6XZsO1;
       spf=pass (google.com: domain of andrey.semashev@gmail.com designates 209.85.220.65 as permitted sender) smtp.mailfrom=andrey.semashev@gmail.com;
       dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
        d=isocpp-org.20150623.gappssmtp.com; s=20150623;
        h=subject:to:references:from:message-id:date:user-agent:mime-version
         :in-reply-to:content-language: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=gC5vu6c9IPIBwzHCGwgcZt8+PUEAnV62gHAdvVJYcSA=;
        b=rQ8TNgjcDjuwB9oPDRD0AOprkjED9kb9FDjaJ27gNh0knTDQ3+L3APmbrGIhqZYYaa
         s7HqPa/df9zeXM3O/DqJHS0aN6qiQmdBSsmP5V6QWmG2T62bbyxjzkE27sJsI1gQFiCo
         AyUids36CbLMNA4GagUALoKxwsNdISH9e6aggM8gzkPdHiX19LpZhpFyLNr33wsfY+3x
         QDcNoivZqPcV+bij3f5iM9QW8ez+3Ih4jDxlMM11lwjwwGqMPfXfBFvtJ/GNbm0HAnn0
         D/Y7/ffItgKx0Vltlh3KltKLiPjm1JIZ8EU9HIVIYDOl26GpDQxInYCJuB92LRigUfpb
         r4BA==
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
        d=1e100.net; s=20161025;
        h=x-gm-message-state:subject:to:references:from:message-id:date
         :user-agent:mime-version:in-reply-to:content-language
         :x-original-sender:x-original-authentication-results:reply-to
         :precedence:mailing-list:list-id:x-spam-checked-in-group:list-post
         :list-help:list-archive:list-subscribe:list-unsubscribe;
        bh=gC5vu6c9IPIBwzHCGwgcZt8+PUEAnV62gHAdvVJYcSA=;
        b=YcaSSb/J5jRUdRz6xHMCeI42tq1kAVnneTUBSpuIuBzZNOjHLPly3TiAajVYKVoRjw
         XvHj4xxke1o2izot2aTtk2K/B1El0wEb+K1669K/88a1Cysk91cmgGb8GWqtCHYoc/RS
         Bm0fi8GxAV1mlqv8aGcGdPtPJ6JKUOLT45+ah14QtJvGpPxJGbiwhdcgwBZySs/PFz4L
         dGEPa69FWPzREitdtmfiVbI8epbjybVqFAfcXPPwsLCto3oPkyZgx9RF4YUxF8vb6PnU
         jHjV64xNQvCyRG7TlOfHjyHmWr6KzCvfnD1TYTHmhVDzQDJESDFKNyw6+qlm065Jxhyg
         U 
X-Gm-Message-State: AElRT7FPm4jmb18AdfohfdJa0caj2U5g5tWe6jjCCLp2D6cVDjHw/GSw
	D6Z6BV5EmL4mUY6wkOdUmanJXw==
X-Google-Smtp-Source: AG47ELsk/WbYvJZnixYmQyTuWm0g7HFmX3Ug6pJPEcT8V15dEeV8c7mJga7VeI9b0/AQD+0ICVlCiA==
X-Received: by 10.46.16.68 with SMTP id j65mr821435lje.37.1521147238699;
        Thu, 15 Mar 2018 13:53:58 -0700 (PDT)
X-BeenThere: std-proposals@isocpp.org
Original-Received: by 2002:a19:9b88:: with SMTP id d130-v6ls632038lfe.11.gmail; Thu, 15
 Mar 2018 13:53:56 -0700 (PDT)
X-Received: by 2002:a19:d945:: with SMTP id q66-v6mr7732181lfg.62.1521147236583;
        Thu, 15 Mar 2018 13:53:56 -0700 (PDT)
ARC-Seal: i=1; a=rsa-sha256; t=1521147236; cv=none;
        d=google.com; s=arc-20160816;
        b=ArIMCUUzf5Xadt4BVl7uzIerzSk9+bv/xTfyP882la5pQw7tshuQe+Z+mCHAczcBz3
         t5teUfmy6+U78952PPb/VkZw9CX2AaeX2WB+k9LjNdlI6ZadfCGz/xd7pplJiWdWOMvk
         5U18dqiGnLzCH/LPmsnCT2c7/LV7ziuMnv8Y0mDvPeBwgnQ+xBqwnr47SIbPTb4j6U3K
         X+YGoqggxNphZc1CGQYrZULrlyqmoajBTDa2mTaRpKFLD8wJhCW2A+2k41Mn1RcSOm4Q
         nC1rnNfLJLOHHK9LnDmNfOe/pmAvVcAlG4UeIdIiEn0Olgml6I3NA70eNRHXAUWD561X
         nlxA==
ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816;
        h=content-transfer-encoding:content-language:in-reply-to:mime-version
         :user-agent:date:message-id:from:references:to:subject
         :dkim-signature:arc-authentication-results;
        bh=pXT7W9iGrjA8pybanXsK0w6BLexqZkUnG9cly8XaIp0=;
        b=0ddO98nhdC5t2C3yCFOoOFnZnRKlNAMq58bJ8MNak6zqbyoBY5xZrRgcrQpugEwJSd
         zulWnULlYQLSAbA+MBk9QIYAxGHqLV2Ca04w43ha16tfYZaQLp3TaC1O06/n8qcNnWv+
         Nk3WpuabXczUXqoXqIWLcDp7n8UbNasFKZIwABJdUvPkHizsdWs0T8L0ibsOpy4dkT6o
         6XhkMdl4kKq8e8BrUfrAVO+GYrnbZlidZ2f2Co1fK0yxbY7xJZq0r1MLwEGn7MnUIxPm
         tDt0Un35h0mULEdc/kQRaHQjNTEYpeMNm3ZwA1EXqCWv5xU8GqyxwdTb7gEIF5f6RYJp
         3ruw==
ARC-Authentication-Results: i=1; mx.google.com;
       dkim=pass header.i=@gmail.com header.s=20161025 header.b=Hu6XZsO1;
       spf=pass (google.com: domain of andrey.semashev@gmail.com designates 209.85.220.65 as permitted sender) smtp.mailfrom=andrey.semashev@gmail.com;
       dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com
Original-Received: from mail-sor-f65.google.com (mail-sor-f65.google.com. [209.85.220.65])
        by mx.google.com with SMTPS id r24sor1271296ljg.3.2018.03.15.13.53.56
        for <std-proposals@isocpp.org>
        (Google Transport Security);
        Thu, 15 Mar 2018 13:53:56 -0700 (PDT)
Received-SPF: pass (google.com: domain of andrey.semashev@gmail.com designates 209.85.220.65 as permitted sender) client-ip=209.85.220.65;
X-Received: by 10.46.64.131 with SMTP id r3mr7530403lje.52.1521147236056;
        Thu, 15 Mar 2018 13:53:56 -0700 (PDT)
Original-Received: from [192.168.1.2] (broadband-109-173-28-102.moscow.rt.ru. [109.173.28.102])
        by smtp.googlemail.com with ESMTPSA id v8sm662570ljj.79.2018.03.15.13.53.54
        for <std-proposals@isocpp.org>
        (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128);
        Thu, 15 Mar 2018 13:53:55 -0700 (PDT)
In-Reply-To: <8745898.m7JMjNCkYK@tjmaciei-mobl1>
Content-Language: en-US
X-Original-Sender: andrey.semashev@gmail.com
X-Original-Authentication-Results: mx.google.com;       dkim=pass
 header.i=@gmail.com header.s=20161025 header.b=Hu6XZsO1;       spf=pass
 (google.com: domain of andrey.semashev@gmail.com designates 209.85.220.65 as
 permitted sender) smtp.mailfrom=andrey.semashev@gmail.com;       dmarc=pass
 (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com
Precedence: list
Mailing-list: list std-proposals@isocpp.org; contact std-proposals+owners@isocpp.org
List-ID: <std-proposals.isocpp.org>
X-Spam-Checked-In-Group: std-proposals@isocpp.org
X-Google-Group-Id: 399137483710
List-Post: <https://groups.google.com/a/isocpp.org/group/std-proposals/post>, <mailto:std-proposals@isocpp.org>
List-Help: <https://support.google.com/a/isocpp.org/bin/topic.py?topic=25838>, <mailto:std-proposals+help@isocpp.org>
List-Archive: <https://groups.google.com/a/isocpp.org/group/std-proposals/>
List-Subscribe: <https://groups.google.com/a/isocpp.org/group/std-proposals/subscribe>,
 <mailto:std-proposals+subscribe@isocpp.org>
List-Unsubscribe: <mailto:googlegroups-manage+399137483710+unsubscribe@googlegroups.com>,
 <https://groups.google.com/a/isocpp.org/group/std-proposals/subscribe>
Xref: news.gmane.org gmane.comp.lang.c++.isocpp.proposals:37346
Archived-At: <http://permalink.gmane.org/gmane.comp.lang.c++.isocpp.proposals/37346>

On 03/15/18 22:41, Thiago Macieira wrote:
> On Thursday, 15 March 2018 10:21:05 PDT Nicolas Lesser wrote:
>> Not that I know of. This was mentioned in passing while discussing P0908,
>> where it was suggested to make it an operator.
> 
> I'd bring back the idea of using pointers to members as a complete replacement
> for offsetof.

P0908 suggested something along these lines and it was rejected.

-- 
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/08d4fa62-ab7d-f257-5a50-fc77f4d35a24%40gmail.com.

.
