From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mga09.intel.com ([134.134.136.24]) by linuxtogo.org with esmtp (Exim 4.72) (envelope-from ) id 1TzrL8-0008UY-Q2 for openembedded-core@lists.openembedded.org; Mon, 28 Jan 2013 17:13:51 +0100 Received: from orsmga001.jf.intel.com ([10.7.209.18]) by orsmga102.jf.intel.com with ESMTP; 28 Jan 2013 07:56:56 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.84,551,1355126400"; d="scan'208";a="253635316" Received: from unknown (HELO helios.localnet) ([10.252.123.209]) by orsmga001.jf.intel.com with ESMTP; 28 Jan 2013 07:58:05 -0800 From: Paul Eggleton To: Enrico Scholz Date: Mon, 28 Jan 2013 15:58:04 +0000 Message-ID: <1440434.Jn4S7oh0Xd@helios> Organization: Intel Corporation User-Agent: KMail/4.9.4 (Linux/3.5.0-22-generic; KDE/4.9.4; i686; ; ) In-Reply-To: References: <1359385200.7131.11.camel@phil-desktop.brightsign> MIME-Version: 1.0 Cc: openembedded-core@lists.openembedded.org Subject: Re: [PATCH 2/2] base: make feature backfilling happen earlier X-BeenThere: openembedded-core@lists.openembedded.org X-Mailman-Version: 2.1.11 Precedence: list List-Id: Patches and discussions about the oe-core layer List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 28 Jan 2013 16:13:57 -0000 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" On Monday 28 January 2013 16:44:15 Enrico Scholz wrote: > Phil Blundell writes: > > This does seem rather like an abuse of DISTRO_FEATURES_BACKFILL. Can > > you explain why you are doing it this way rather than just setting > > DISTRO_FEATURES directly to what you wanted? > > I need a way to: > > 1. set some defaults on distribution base and avoid nasty details like > mandatory ${DISTRO_FEATURES_LIBC} flags in the project configuration > > 2. allow to override these defaults on a per-project base > > 3. add features support by recipes/classes of my distribution > > afaik, DISTRO_FEATURES_BACKFILL + _CONSIDERED exist to allow the first > two point without an '-=' operator which lacks in bitbake. No they don't. They exist to allow adding new features that should be enabled for all existing distro configs without each of those having to be changed, and provide a means for distros to opt out of that enabling if they wish. > Of course, I could reinvent the wheel and write my own _CONSIDERED > mechanism. But until now (resp. without the '=' => '?=' change), it > worked fine with DISTRO_FEATURES_BACKFILL. We don't support using the backfill mechanism in this manner; so if it breaks you get to keep both pieces. It's still not clear to me why you could not just set DISTRO_FEATURES directly. If you have values you're likely to want to remove, you can put them in separate variables that you can clear out later. Cheers, Paul -- Paul Eggleton Intel Open Source Technology Centre