From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga03.intel.com (mga03.intel.com [134.134.136.65]) by dpdk.org (Postfix) with ESMTP id 274A5137C for ; Fri, 30 Sep 2016 16:33:03 +0200 (CEST) Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by orsmga103.jf.intel.com with ESMTP; 30 Sep 2016 07:33:01 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.31,272,1473145200"; d="scan'208";a="767567604" Received: from fyigit-mobl1.ger.corp.intel.com (HELO [10.237.221.70]) ([10.237.221.70]) by FMSMGA003.fm.intel.com with ESMTP; 30 Sep 2016 07:33:01 -0700 To: Adrien Mazarguil , Bruce Richardson References: <1474295814-4879-1-git-send-email-bruce.richardson@intel.com> <20160919145959.GB17252@6wind.com> <20160919152605.GG45548@bricha3-MOBL3> <20160920125126.GG17252@6wind.com> <20160920155848.GA74952@bricha3-MOBL3> <20160920181751.GJ17252@6wind.com> Cc: dev@dpdk.org From: Ferruh Yigit Message-ID: <78fe6c4a-b57a-a4e5-5317-29d4b1238023@intel.com> Date: Fri, 30 Sep 2016 15:33:00 +0100 User-Agent: Mozilla/5.0 (Windows NT 6.3; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.3.0 MIME-Version: 1.0 In-Reply-To: <20160920181751.GJ17252@6wind.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Subject: Re: [dpdk-dev] [PATCH] net/mlx: fix compile errors with ignore pedantic pragma X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 30 Sep 2016 14:33:03 -0000 On 9/20/2016 7:17 PM, Adrien Mazarguil wrote: > On Tue, Sep 20, 2016 at 04:58:48PM +0100, Bruce Richardson wrote: >> On Tue, Sep 20, 2016 at 02:51:27PM +0200, Adrien Mazarguil wrote: >>> On Mon, Sep 19, 2016 at 04:26:05PM +0100, Bruce Richardson wrote: >>>> On Mon, Sep 19, 2016 at 04:59:59PM +0200, Adrien Mazarguil wrote: >>>>> Hi Bruce, >>>>> >>>>> On Mon, Sep 19, 2016 at 03:36:54PM +0100, Bruce Richardson wrote: >>>>>> With recent gcc versions, e.g. gcc 6.1, compilation of mlx drivers with >>>>>> debug enabled produces lots of errors complaining that "pedantic" is >>>>>> not a warning level that can be ignored. >>>>>> >>>>>> error: ‘-pedantic’ is not an option that controls warnings [-Werror=pragmas] >>>>>> #pragma GCC diagnostic ignored "-pedantic" >>>>>> ^~~~~~~~~~~ >>>>>> >>>>>> These errors can be removed by changing the "-pedantic" to "-Wpedantic". >>>>> >>>>> Nice to have a workaround, I thought they did not keep the option at all. >>>>> However after testing: >>>>> >>>>> - It does not seem to work with GCC 4.6 and older, they prefer -pedantic: >>>>> "warning: unknown option after `#pragma GCC diagnostic' kind". >>>>> >>>>> - GCC 4.9 (possibly 5.x as well) does not care, can use either -pedantic or >>>>> -Wpedantic. >>>>> >>>>> - GCC 6 can only supports -Wpedantic. >>>>> >>>>> Note we're working toward removing the need for these #pragma in the first >>>>> place as soon as possible, however in the meantime I fear that checking the >>>>> GCC version is necessary. >>>>> >>>> Depends on how old of GCC version we need to support. From the release notes >>>> it appears that -Wpedantic was introduced in GCC 4.8 (3 1/2 years ago). >>>> >>>> https://gcc.gnu.org/gcc-4.8/changes.html >>>> >>>> Do we need to support compilation on gcc versions older than this? >>> >>> I'm all for upgrading so I do not really mind if we stop caring about older >>> GCC versions (especially considering this problem only occurs in debugging >>> mode which is seldom used by non-developers). The version check is necessary >>> if we want to keep full compatibility with at least: >>> >>> - RHEL <= 6.x >>> - Debian <= 7.x >>> - Ubuntu <= 13.04 >>> >>> Works for me either way, thus: >>> >>> Acked-by: Adrien Mazarguil >>> >> Any objections to dropping of support for debug settings for these OS's? > > Not sure who should answer this. These #pragma are workarounds we should > eventually get rid of anyway (DPDK headers are now clean enough, some work > remains to be done on the Verbs side) so let's use your patch in the > meantime. > Just as a quick note, this breaks compilation for ICC: .../drivers/net/mlx4/mlx4.c(64): error #2282: unrecognized GCC pragma #pragma GCC diagnostic ignored "-Wpedantic" Since this compilation error only happens for MLX4/5 when debug config option enabled, this not big issue, but please aware of the issue. Thanks, ferruh