From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from proxy.dresearch.de ([87.193.137.100] helo=mail.dresearch.de) by linuxtogo.org with esmtp (Exim 4.72) (envelope-from ) id 1PpMFl-0000WQ-FG for openembedded-devel@lists.openembedded.org; Tue, 15 Feb 2011 15:51:45 +0100 Received: from exchange.intern.dresearch.de (owa.xfer-intern.dresearch.de [192.168.32.16]) by mail.dresearch.de (Postfix) with ESMTP id 2E76D491286; Tue, 15 Feb 2011 15:50:37 +0100 (CET) Received: from [127.0.0.1] ([10.32.10.2]) by exchange.intern.dresearch.de with Microsoft SMTPSVC(6.0.3790.4675); Tue, 15 Feb 2011 15:50:37 +0100 Message-ID: <4D5A92BC.1010906@dresearch.de> Date: Tue, 15 Feb 2011 15:50:36 +0100 From: Steffen Sledz User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; de; rv:1.9.2.13) Gecko/20101207 Lightning/1.0b2 Thunderbird/3.1.7 MIME-Version: 1.0 To: openembedded-devel@lists.openembedded.org References: <4D5A5871.7000005@dresearch.de> <4D5A89CD.803@opendreambox.org> In-Reply-To: <4D5A89CD.803@opendreambox.org> X-OriginalArrivalTime: 15 Feb 2011 14:50:37.0243 (UTC) FILETIME=[B4DFB0B0:01CBCD1F] Subject: Re: linux-libc-headers version (reloaded) X-BeenThere: openembedded-devel@lists.openembedded.org X-Mailman-Version: 2.1.11 Precedence: list Reply-To: openembedded-devel@lists.openembedded.org List-Id: Using the OpenEmbedded metadata to build Distributions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 15 Feb 2011 14:51:45 -0000 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Am 15.02.2011 15:12, schrieb Andreas Oberritter: > On 02/15/2011 11:41 AM, Steffen Sledz wrote: >> "Kernel headers are backwards compatible, but not forwards compatible.= This >> means that a program built against a C library using older kernel head= ers >> should run on a newer kernel (although it may not have access to new >> features), but a program built against newer kernel headers may not wo= rk on an >> older kernel."[2] >=20 > Isn't this what the variable OLDEST_KERNEL is good for, when compiling > glibc? If i'm right this goes to the --enable-kernel=3DVERSION configure option = of glibc just to optimize the library. "the configure option --enable-kernel=3DX.Y.Z allows to strip out compati= bility for kernel versions before X.Y.Z." Imho it is not legitimately to follow that glibc has compatibility code f= or all kernels greater or equal X.Y.Z. Another question is the handling in other libc implementations. And finally there are a lot of programs using userland kernel headers dir= ectly. Steffen --=20 DResearch Fahrzeugelektronik GmbH Otto-Schmirgal-Str. 3, 10319 Berlin, Germany Tel: +49 30 515932-237 mailto:sledz@DResearch.de Fax: +49 30 515932-299 Gesch=E4ftsf=FChrer: Dr. Michael Weber, Werner M=F6gle; Amtsgericht Berlin Charlottenburg; HRB 130120 B; Ust.-IDNr. DE273952058