From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by yocto-www.yoctoproject.org (Postfix, from userid 118) id 7E27DE0043F; Fri, 18 Jul 2014 08:38:04 -0700 (PDT) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on yocto-www.yoctoproject.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 X-Spam-HAM-Report: * -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% * [score: 0.0000] * -5.0 RCVD_IN_DNSWL_HI RBL: Sender listed at http://www.dnswl.org/, high * trust * [192.94.94.40 listed in list.dnswl.org] Received: from arroyo.ext.ti.com (arroyo.ext.ti.com [192.94.94.40]) by yocto-www.yoctoproject.org (Postfix) with ESMTP id 4A346E00342 for ; Fri, 18 Jul 2014 08:37:54 -0700 (PDT) Received: from dflxv15.itg.ti.com ([128.247.5.124]) by arroyo.ext.ti.com (8.13.7/8.13.7) with ESMTP id s6IFbm8F014381; Fri, 18 Jul 2014 10:37:48 -0500 Received: from DLEE70.ent.ti.com (dlee70.ent.ti.com [157.170.170.113]) by dflxv15.itg.ti.com (8.14.3/8.13.8) with ESMTP id s6IFbmWR018144; Fri, 18 Jul 2014 10:37:48 -0500 Received: from dlep33.itg.ti.com (157.170.170.75) by DLEE70.ent.ti.com (157.170.170.113) with Microsoft SMTP Server id 14.3.174.1; Fri, 18 Jul 2014 10:37:47 -0500 Received: from localhost (ileax41-snat.itg.ti.com [10.172.224.153]) by dlep33.itg.ti.com (8.14.3/8.13.8) with ESMTP id s6IFblvC007227; Fri, 18 Jul 2014 10:37:47 -0500 Date: Fri, 18 Jul 2014 11:37:47 -0400 From: Denys Dmytriyenko To: "Robert P. J. Day" Message-ID: <20140718153747.GF15788@edge> References: MIME-Version: 1.0 In-Reply-To: User-Agent: Mutt/1.5.20 (2009-06-14) Cc: meta-ti mailing list Subject: Re: curious about libdrm-2.4.41 recipe from meta-ti layer X-BeenThere: meta-ti@yoctoproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: Usage and development list for the meta-ti layer List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 18 Jul 2014 15:38:04 -0000 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline On Fri, Jul 18, 2014 at 07:46:36AM -0400, Robert P. J. Day wrote: > > i was perusing a number of yocto layers looking for cool examples to > use in an upcoming class and ran across this oddity in the meta-ti > layer: > > recipes-graphics/drm/libdrm_2.4.41.bb: > FILESEXTRAPATHS_append := ":${COREBASE}/meta/recipes-graphics/drm/libdrm" > > in all of the layers i've looked at, that is the only example of > *appending* to FILESEXTRAPATHS i've ever seen, so i thought i'd look > closer to see what was going on. > > even though oe-core defines a libdrm recipe file, the meta-ti layer > doesn't use a bbappend for its version. rather, it explicitly adds the > libdrm/ directory from oe-core using a reference to ${COREBASE}, then > adds its own files. that's valid, i guess, it just looks weird and is > the only time i've ever seen that. > > i'm also puzzled that the meta-ti recipe sets: > > DEFAULT_PREFERENCE = "-1" > > what's that for? given that the oe-core layer already defines a > recipe for libdrm that has a higher version number, why would the > above line be necessary? > > just trying to understand the rationale behind this unusual > construction. You missed line #11 with custom SRC_URI, which points to a forked and modified sources of a very specific version of libdrm for one platform. That's why it sets COMPATIBLE_MACHINE and DEFAULT_PREFERENCE - it needs to be requested specifically and not selected automatically by accident. By default we want to use the latest upstream version from oe-core. And it cannot be made as a bbappend - it provides a different version than oe-core. But it reuses GNU_SOURCE_definition.patch from oe-core, hence FILESEXTRAPATHS mangling. Don't ask why it's done with forked git sources instead of patches though - not my decision :) -- Denys