From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=stwcx.xyz (client-ip=66.111.4.27; helo=out3-smtp.messagingengine.com; envelope-from=patrick@stwcx.xyz; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=stwcx.xyz Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=stwcx.xyz header.i=@stwcx.xyz header.a=rsa-sha256 header.s=fm2 header.b=Jlb5grVt; dkim=pass (2048-bit key; unprotected) header.d=messagingengine.com header.i=@messagingengine.com header.a=rsa-sha256 header.s=fm2 header.b=oWNDp7Wr; dkim-atps=neutral Received: from out3-smtp.messagingengine.com (out3-smtp.messagingengine.com [66.111.4.27]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 49c3724TsWzDqWp for ; Wed, 3 Jun 2020 06:10:05 +1000 (AEST) Received: from compute7.internal (compute7.nyi.internal [10.202.2.47]) by mailout.nyi.internal (Postfix) with ESMTP id A45DA5C0129; Tue, 2 Jun 2020 16:10:01 -0400 (EDT) Received: from mailfrontend2 ([10.202.2.163]) by compute7.internal (MEProxy); Tue, 02 Jun 2020 16:10:01 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=stwcx.xyz; h= date:from:to:cc:subject:message-id:references:mime-version :content-type:in-reply-to; s=fm2; bh=njYxnFdyYdYfmF8+AjrCV56i83y S4oKyvDZN0UgxgpY=; b=Jlb5grVtn8II8DViMEpMwULQ25tFJOym3g7wYEekNdL MytvVhAO6qyfV9hFK/b8LySFjlA3shyzRa1BSO8kjCTjLOHrKZ6kJjBiVGH/P1w2 oZyVjLH7XP96EikqoO0j0U3ziQNZIJ8az235XvtFG5bCMIT2Oc9t+Vk2aviSyv76 k5gp2nuvO9ROHNdgDZGacRILXcQ83fFopSkkFv3XeotDo0BQ3qY8QeHwsNsXBEQ3 0Js+X3ZI/PbHZ8qGDjdUU18CBQmdOoIEx845xx0iBLWo7IwpqlqUP0PDrDAvU6Fb 3L+X/XgAi3WyvOGtKRUA83lU57cK8W1gQGcHS0kN2SA== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to:x-me-proxy :x-me-proxy:x-me-sender:x-me-sender:x-sasl-enc; s=fm2; bh=njYxnF dyYdYfmF8+AjrCV56i83yS4oKyvDZN0UgxgpY=; b=oWNDp7WrVv46W1shCeA56L aiG7E8L3UxijACbxgRQlmz/h7e31ujeBytz9VGa1g9713BoOS6j0AkVostM+nQIS VV2RPGB82MtyYpXCREhey0I1dAt9rU13FDdVx2yS7raKXqYH2ATVzGlSc1YFKqhH tYSk5/3X4KjKd/c6IcLEocbwN/SJc/YjiC+khT3yKsMa/z2oFUBven3JqpM+34So THiYcKwCDMBYOWFfvwPa4U7QnglCwwsLcLM0Tepbq6BTb1g6urAEriOkZKPD6++i E2UX3zXbpm3nKnGKhsI26GSxqNZ3n3iaY8nzHouBT2vhQlDBC/uAzoAHnmeumMqA == X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgeduhedrudefjedgudduudcutefuodetggdotefrod ftvfcurfhrohhfihhlvgemucfhrghsthforghilhdpqfgfvfdpuffrtefokffrpgfnqfgh necuuegrihhlohhuthemuceftddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmd enfghrlhcuvffnffculdefhedmnecujfgurhepfffhvffukfhfgggtuggjsehgtderredt tddunecuhfhrohhmpefrrghtrhhitghkucghihhllhhirghmshcuoehprghtrhhitghkse hsthiftgigrdighiiiqeenucggtffrrghtthgvrhhnpeettefhffeuveekhfdvgfevhefh ueffhfegffejvdekteefffefheelhfevudeuudenucffohhmrghinhepghhnuhdrohhrgh enucfkphepudeiiedrudejiedruddvtddrkeeknecuvehluhhsthgvrhfuihiivgeptden ucfrrghrrghmpehmrghilhhfrhhomhepphgrthhrihgtkhesshhtfigtgidrgiihii X-ME-Proxy: Received: from localhost (mobile-166-176-120-88.mycingular.net [166.176.120.88]) by mail.messagingengine.com (Postfix) with ESMTPA id D89F43060FE7; Tue, 2 Jun 2020 16:09:59 -0400 (EDT) Date: Tue, 2 Jun 2020 15:09:58 -0500 From: Patrick Williams To: "Khetan, Sharad" Cc: Adrian =?utf-8?Q?Ambro=C5=BCewicz?= , OpenBMC Maillist Subject: Re: Upstream Yocto Bringing in GCC 10 Message-ID: <20200602200958.GI17541@heinlein> References: <9871E71B-5B1F-4172-9F41-454F8C1F644D@gmail.com> <20200518000811.GI1166713@heinlein> <2E02F120-7D24-48BE-AFD8-9A7ADD0F08E5@gmail.com> <7f027233-e0c5-552d-82da-cd3a30d74009@linux.intel.com> <20200526155756.GC3445@heinlein> <78ffc9e9-816a-c420-2d51-8a635342e3c4@linux.intel.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="2nTeH+t2PBomgucg" Content-Disposition: inline In-Reply-To: X-BeenThere: openbmc@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Development list for OpenBMC List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 02 Jun 2020 20:10:11 -0000 --2nTeH+t2PBomgucg Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Tue, Jun 02, 2020 at 06:32:34PM +0000, Khetan, Sharad wrote: > From: openbmc On Behalf Of Adrian Ambrozewicz > Sent: Tuesday, June 02, 2020 1:19 AM > W dniu 5/26/2020 o=A017:57, Patrick Williams pisze: > >I can imagine some companies or communities might choose to be careful i= n that matter. I was just wondering if there is some 'BKM' which states 'ex= perimental (unstable?) implementations are prohibited from use until marked= by software vendor as stable'. Maybe that's my problem - I could be confus= ing 'experimental' with 'unstable' after all:) >=20 > If experimental means potentially unstable, I would say we avoid such imp= lementation in the OpenBMC. We need to keep OpenBMC stable and such new lan= guage / compiler features may be pretty gnarly to debug by the users. Just a few thoughts: 1. We've not historically had this distinction / restriction. We've tended to use the latest C++ standard soon after it is available in our Yocto compiler toolchain and even used std::experimental pieces. * Yocto supported GCC7 (C++17 support) in April 2018 and we enabled it in October 2018. * We used mapbox::variant with C++14, which was a C++14 * implementation of the proposed C++17 API, and then used std::variant when it was available. * We still have code referring to std::experimental::filesystem which has almost identical API as std::filesystem. 2. "Vendors" don't really give us an indication of stability, so we'd need to define one. Today, GCC's C++20 status is a simple "no support" (red), "partial support" (yellow), "done" (green). Most of the C++20 support is in GCC-10 which we are now using. * https://gcc.gnu.org/projects/cxx-status.html 3. I suspect most of our locally written code is "less stable" than anything coming out of GCC simply by nature of how many users and tests they have. Most of the C++ features accepted by the standard committees have an implementation in at least 1 of the big 3 compilers (MS-VS, GCC, Clang) and so there is code around to use for test suites. --=20 Patrick Williams --2nTeH+t2PBomgucg Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAABCAAdFiEEBGD9ii4LE9cNbqJBqwNHzC0AwRkFAl7WshQACgkQqwNHzC0A wRlBSBAAngjWiOBAomGkHAumkoV4Ip45fmUmsYcgQSiEPfN9OH51sznae4suqm5i dM7bKRqmgCUpnelfe5LsSI6os6TUVd7lwhkgnuNrNaX2s1gwoqLRj+SnpdDHApIB 0fNdCT6i7vWagWdMhGWX5/JcdO3pBG/fdWeczmXRr6Lq1GLRWoT04BbbfaJVnmda UqAewp3kp9spTevtBsYkTbyNX5FYHuJQoa25Kz6J+/INdVQKOMFe2Jmi6iBfkGLr C7QZ+WECA4iXoBoz6QW/U/8y9okjAWczazfzSJU3/VJUoUHsITSxydSrqrcjxAyT A9KZlDlpESdkkUOZzsgsZiFvj9XnugLtqDnUBZRc74LWU6iPaH2jpgE04ZG77+A9 2NBpz6kZgQ4FWhBLuqC6lv16RFASpvzRWNCa2m3rNYjw1LJwb/+VKAwC32CQV3gg LDJKmt/up3yjhFPwh7rCNe5AH+mn3o1+jq8pHCxIN8Q4ybj11TDagYsq9lvnpe2Q 0d6Ad5V8OT8+RpAvR+YFPTKvDatAW3ag0GOtXoalldh5asXzQ+YBJUphVJ90ouYO 6+i3PLASZ1+wKJIVytPpSpv0ePy7N++YW/Hcfsd/sZKHMPs8RIUuxauJ+ekrUJzK eNXOEC2+/TZEg1FEndIKHGCq4r+6b4jhK1s6s/AiO8Qec6JUmEY= =lghy -----END PGP SIGNATURE----- --2nTeH+t2PBomgucg--