220 12370 <4696439.EtcWScoEnF@tjmaciei-mobl4> article Path: news.gmane.org!not-for-mail From: Thiago Macieira Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Crypto-hash obfuscated namespaces Date: Wed, 20 Aug 2014 08:38:03 -0500 Lines: 52 Approved: news@gmane.org Message-ID: <4696439.EtcWScoEnF@tjmaciei-mobl4> References: <1982042.YnJ2Uhn0rL@tjmaciei-mobl4> <43CE2885-EE77-4A34-BB85-585BF30AB9AF@gmail.com> Reply-To: std-proposals@isocpp.org NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 X-Trace: ger.gmane.org 1408541939 24175 80.91.229.3 (20 Aug 2014 13:38:59 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Wed, 20 Aug 2014 13:38:59 +0000 (UTC) To: std-proposals@isocpp.org Original-X-From: std-proposals+bncBCB4TK757YBRBYOJ2KPQKGQEB2XDPHY@isocpp.org Wed Aug 20 15:38:55 2014 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-we0-f199.google.com ([74.125.82.199]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1XK666-0008HE-Ne for gclcip-std-proposals@m.gmane.org; Wed, 20 Aug 2014 15:38:42 +0200 Original-Received: by mail-we0-f199.google.com with SMTP id p10sf4943483wes.2 for ; Wed, 20 Aug 2014 06:38:42 -0700 (PDT) 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:x-original-sender :x-original-authentication-results:reply-to:precedence:mailing-list :list-id:list-post:list-help:list-archive:list-subscribe :list-unsubscribe:content-type; bh=umaILfvCS0ScLvbwKNNJfeYD4b6NmlgMYrOrHNYkNCc=; b=BNtZ1a6PRifIcHOvfn2OFu1vUqfg+Nq+XR2l/j9zsPTaZDgaDnDh1/Jy6pUMIwsBh6 9DOW9MyD0wpxi+KXDDYkoHuikpwa2r3oqx1Ls3vK2C10PKI2DN9txZAtINJkP9isNoZ6 8CzGw39fl+4JAgMYLp8x9Oed0rjjMz/mq9+WiwlUs2rGSPPO8VeMHR3ZbYaBrP9gXIXq Ddsn5MYtUumhleAiO5vtiFkvFn5TmDvmY82pjxMV8xA+RpXoti3EjqdPi9hC5Q4Fi5oT ejwLAQP7Ppg/M+RoOrFgjin3QrB+l6uCqCmQ+tUhaRziD9A4FVbbosm5pJhJp4+LVlOa tjjg== X-Gm-Message-State: ALoCoQkkfBDFByAFVXYWfyXXp2R0a+eEtzBklEM0X4LJ9WIjjuciLoku45KYpSsBz+LAtOgXJPF9 X-Received: by 10.194.2.130 with SMTP id 2mr290603wju.5.1408541922387; Wed, 20 Aug 2014 06:38:42 -0700 (PDT) X-BeenThere: std-proposals@isocpp.org Original-Received: by 10.152.183.233 with SMTP id ep9ls62562lac.62.gmail; Wed, 20 Aug 2014 06:38:40 -0700 (PDT) X-Received: by 10.152.179.168 with SMTP id dh8mr42944976lac.0.1408541920790; Wed, 20 Aug 2014 06:38:40 -0700 (PDT) Original-Received: from gondolin.macieira.info (gondolin.macieira.info. [2a01:4f8:d13:f81:21c:14ff:fe01:12a3]) by mx.google.com with ESMTP id ui10si34220962lbc.100.2014.08.20.06.38.40 for ; Wed, 20 Aug 2014 06:38:40 -0700 (PDT) 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 (jfdmzpr06-ext.jf.intel.com [134.134.137.75]) by gondolin.macieira.info (Postfix) with ESMTPSA id B1B7412C00A for ; Wed, 20 Aug 2014 06:38:39 -0700 (PDT) User-Agent: KMail/4.14 beta2 (Linux/3.11.10-17-desktop; KDE/4.13.90; x86_64; ; ) In-Reply-To: <43CE2885-EE77-4A34-BB85-585BF30AB9AF@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:12370 Archived-At: On Wednesday 20 August 2014 18:01:14 David Krauss wrote: > On 2014-08-20, at 3:27 PM, Thiago Macieira wrote: > > This doesn't look like it needs to be standardised at all. The standard > > doesn't require that typeinfo carry a readable name. It's only required to > > be unique per type (the portable C++ ABI carries the mangled name). > > The standard also requires no attributes on namespaces. > > I already mentioned that the attribute could otherwise be a conforming > extension. > > Actually, to be thorough, it's the mangled name that should be replaced with > a hash. Object and function names still get exposed by shared libraries. > This wouldn't work well on implementations that require shared library > exports to be specified as a list of mangled names, but that's poor QOI > anyway. > On 2014-08-20, at 4:57 PM, Andrew Tomazos wrote: > > The name isn't required to be unique per type. An implementation may > > return the empty string for all types for example, provided this behavior > > was documented. (See 18.7.1 [type.info]) > Perhaps, but an implementation providing for hashes of user-specified length > could allow the length to be zero and then emit empty strings. I suppose it > depends on how the RTTI implementation uses the strings, for example for > type_info::before. If it really can tolerate absence of string data, then > that would be an optimal solution. > > Anything besides the common ABI is a no-go without some way to opt in. On > second thought, extern "C++ obfuscated" would also do the trick, but I > think attributes are preferable. External names are not part of the C++ standard. So let's forget everything about symbols here. I think the only thing we can take out of your proposal here is that attributes should be allowed on namespaces. Everything else is going to be compiler- and ABI-specific. -- 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 -- --- 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. Visit this group at http://groups.google.com/a/isocpp.org/group/std-proposals/. .