220 38237 <09b7df78-9694-896f-dc0c-e3e5f5ac3c42@gmail.com> article Path: news.gmane.org!.POSTED!not-for-mail From: Andrey Semashev Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Re: memcpy/memset/etc overloads for volatile memory Date: Mon, 28 May 2018 18:47:10 +0300 Lines: 31 Approved: news@gmane.org Message-ID: <09b7df78-9694-896f-dc0c-e3e5f5ac3c42@gmail.com> References: <420b274b-fc4b-413e-8ce9-b78131c782f7@isocpp.org> <5B0BFB66.7080501@gmx.net> 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 1527522307 16176 195.159.176.226 (28 May 2018 15:45:07 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Mon, 28 May 2018 15:45:07 +0000 (UTC) User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.8.0 To: std-proposals@isocpp.org Original-X-From: std-proposals+bncBCXY5TXHWYJRBAOJWDMAKGQEAT3W2FQ@isocpp.org Mon May 28 17:45:02 2018 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-wr0-f198.google.com ([209.85.128.198]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1fNKKU-00048Q-U1 for gclcip-std-proposals@m.gmane.org; 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[178.140.223.238]) by smtp.googlemail.com with ESMTPSA id j15-v6sm6928077lfh.72.2018.05.28.08.47.11 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 28 May 2018 08:47:11 -0700 (PDT) In-Reply-To: <5B0BFB66.7080501@gmx.net> 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=LlOnq+/0; 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: 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:38237 Archived-At: On 05/28/18 15:51, Jens Maurer wrote: > On 05/28/2018 01:09 AM, Niall Douglas wrote: >> Just there this weekend I, yet again, had to write a custom memcpy() >> implementation because the built-in one can be elided by the compiler >> during optimisation. I'd like to stop having to write memcpy() >> personally. >> >> I think your idea has two variants: >> >> 1. Cannot be optimised out memcpy/memset/memmove etc. I'd suggest >> secure_memset(), secure_memcpy(), secure_memmove() and so on rather >> than editions taking a volatile pointer. > > ISO C11 has memset_s in K.3.7.4.1. Annex K is basically dead and is considered for for removal, as I heard. There are a few non-portable replacements, though. http://netbsd.gw.com/cgi-bin/man-cgi?explicit_memset+3+NetBSD-current https://manpages.debian.org/testing/manpages-dev/bzero.3.en.html Having a portable equivalent of explicit_memset & co. in the standard (but not Annex K) would be really useful. -- 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/09b7df78-9694-896f-dc0c-e3e5f5ac3c42%40gmail.com. .