From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx2.suse.de (mx2.suse.de [195.135.220.15]) by dpdk.org (Postfix) with ESMTP id A877A559C for ; Tue, 22 Mar 2016 23:50:58 +0100 (CET) X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay1.suse.de (charybdis-ext.suse.de [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id B1F9AABB0; Tue, 22 Mar 2016 22:50:09 +0000 (UTC) To: Thomas Monjalon References: <1458666816-29778-1-git-send-email-mchandras@suse.de> <2653966.ML0Fr8PsdQ@xps13> Cc: dev@dpdk.org From: Markos Chandras Message-ID: <56F1CC20.50707@suse.de> Date: Tue, 22 Mar 2016 22:50:08 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.7.0 MIME-Version: 1.0 In-Reply-To: <2653966.ML0Fr8PsdQ@xps13> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 8bit X-Mailman-Approved-At: Wed, 23 Mar 2016 09:26:45 +0100 Subject: Re: [dpdk-dev] [PATCH] mk: toolchain: gcc: query the compiler macros to obtain the gcc version 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: Tue, 22 Mar 2016 22:50:59 -0000 Hi, On 22/03/16 22:34, Thomas Monjalon wrote: > 2016-03-22 17:13, Markos Chandras: >> This is similar to what's being used in the Linux kernel. Querying the >> GCC macros directly gives more accurate results compared to -dumpversion >> which could vary across distributions. >> >> Signed-off-by: Markos Chandras >> --- >> In openSUSE Tumbleweed (and in any other SUSE distribution which >> uses (or will use) gcc >= 5), gcc -dumpversion returns '5'. This is on >> purpose as discussed in https://bugzilla.opensuse.org/show_bug.cgi?id=941428 > > Good to know. It could be in the commit log. I can add this information to the commit message and send a v2 if needed. > >> -GCC_VERSION = $(subst .,,$(shell $(CC) -dumpversion | cut -f1-2 -d.)) >> +GCC_MAJOR = $(shell echo __GNUC__ | $(CC) -E -x c - | tail -n 1) >> +GCC_MINOR = $(shell echo __GNUC_MINOR__ | $(CC) -E -x c - | tail -n 1) >> +GCC_VERSION = $(GCC_MAJOR)$(GCC_MINOR) > > Are we sure the minor will always be only one digit? > Well, I can't be sure but minor has always been a single digit since gcc >= 3 if I am not mistaken. But does it matter? What if it is two or more digits? The previous code did something similar so if you had gcc 5.12.34 installed (and lets assume this is what is being returned by -dumpversion), it would have returned 512. The comparison would still work as it is at the moment no? -- markos