From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by inbox.dpdk.org (Postfix) with ESMTP id 61BC041C62; Sat, 11 Feb 2023 00:39:44 +0100 (CET) Received: from mails.dpdk.org (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id E1E3640E50; Sat, 11 Feb 2023 00:39:43 +0100 (CET) Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by mails.dpdk.org (Postfix) with ESMTP id A2C4440E0F for ; Sat, 11 Feb 2023 00:39:41 +0100 (CET) Received: by linux.microsoft.com (Postfix, from userid 1086) id C71A720C8B18; Fri, 10 Feb 2023 15:39:40 -0800 (PST) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com C71A720C8B18 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1676072380; bh=hQ69xlnK2xUnuI36d2Hhf3Za7iN0YHmWmy+5NgAFUqo=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=axCMJ/Ce/3+YX95XT2nkQObVNBqTQWC8CiQH1oG2pJ50Mbp9kYagCm8S9BnYFmAQQ 2vl1CVdzDoQfdVemyn75cLbNZ4EkizMfrqyKt/L0lA4llN7uw6U3gk2xYEpxsEboxX ltuEIb9UqcIdKhh3tfNPkkKT1xjz6WKn7KL6ExeU= Date: Fri, 10 Feb 2023 15:39:40 -0800 From: Tyler Retzlaff To: Ben Magistro Cc: Bruce Richardson , dev@dpdk.org, thomas@monjalon.net, david.marchand@redhat.com, mb@smartsharesystems.com Subject: Re: [RFC PATCH 0/1] Specify C-standard requirement for DPDK builds Message-ID: <20230210233940.GA29685@linuxonhyperv3.guj3yctzbm1etfxqx2vob5hsef.xx.internal.cloudapp.net> References: <20230112113556.47485-1-bruce.richardson@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org On Fri, Feb 10, 2023 at 09:52:06AM -0500, Ben Magistro wrote: > Adding Tyler > > Sort of following along on the RFC: introduce atomics [1] it seems like the > decision to use 99 vs 11 here could make an impact on the approach taken in > that thread. hey Ben thanks for keeping an eye across threads on the topic. the atomics thread is fairly long but somewhere in it i did provide a rationale for why we can't just go straight to using C11 even if we declared that dpdk on supports compilers >= C11. i wish we could it would certainly make my life way easier if i could just -std=c11 and cut & paste my way to completion. the reason why we can't (aside from not requiring C11 compiler as a minimum) is that there is potential issue with abi compatibility for existing applications using non-atomic types currently passed to ABI suddenly requiring standard atomic types. this is because _Atomic type and type are not guaranteed to have the same size, alignment, representation etc.. anyway, i welcome us establishing c99 as a minimum for all toolchain/platform combinations. > > 1) http://mails.dpdk.org/archives/dev/2023-February/262042.html > > On Fri, Feb 3, 2023 at 1:00 PM Bruce Richardson > wrote: > > > On Fri, Feb 03, 2023 at 11:45:04AM -0500, Ben Magistro wrote: > > > In our case we have other libraries that we are using that have > > > required us to specify a minimum c++ version (14/17 most recently for > > > one) so it doesn't feel like a big ask/issue to us (provided things > > > don't start conflicting...hah; not anticipating any issue). Our > > > software is also used internally so we have a fair bit of control over > > > how fast we can adopt changes. > > > This got me wondering what some other projects in the DPDK ecosystem > > > are saying/doing around language standards/gcc versions. So some > > quick > > > checking of the projects I am aware of/looked at/using... > > > * trex: cannot find an obvious minimum gcc requirement > > > * tldk: we are running our own public folk with several fixes, need to > > > find time to solve the build sys change aspect to continue providing > > > patches upstream; I know I have hit some places where it was easier to > > > say the new minimum DPDK version is x at which point you just adopt > > the > > > minimum requirements of DPDK > > > * ovs: looks to be comfortable with an older gcc still > > > * seastar: seems to be the most aggressive with adopting language > > > standards/compilers I've seen [1] and are asking for gcc 9+ and cpp17+ > > > * ans: based on release 19.02 (2019), they are on gcc >= 5.4 [2] and > > is > > > the same on the main README file > > > I do understand the concern, but if no one is voicing an > > > opinion/objection does that mean they agree with/will not be affected > > > by the change.... > > > 1) [1]https://docs.seastar.io/master/md_compatibility.html > > > 2) [2]https://github.com/ansyun/dpdk-ans/releases > > > Cheers > > > > > Thanks for the info. > > I also notice that since gcc 5, the default language version used - if none > > is explicitly specified - is gnu11 (or higher for later versions). Clang > > seems to do something similar, but not sure at what point it started > > defaulting to a standard >=c11. > > > > /Bruce > >