From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752772AbbJLVzq (ORCPT ); Mon, 12 Oct 2015 17:55:46 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:34017 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752738AbbJLVzo (ORCPT ); Mon, 12 Oct 2015 17:55:44 -0400 Date: Mon, 12 Oct 2015 14:55:42 -0700 From: Andrew Morton To: Jim Davis Cc: Stephen Rothwell , linux-next , linux-kernel , yalin.wang2010@gmail.com Subject: Re: randconfig build error with next-20151009, in lib/zlib_deflate/deftree.c Message-Id: <20151012145542.f1ea33ea2e5a0407b667a9e8@linux-foundation.org> In-Reply-To: References: X-Mailer: Sylpheed 3.4.1 (GTK+ 2.24.23; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 9 Oct 2015 13:38:25 -0700 Jim Davis wrote: > Building with the attached random configuration file, > > lib/built-in.o: In function `__bitrev32': > deftree.c:(.text+0x1e799): undefined reference to `byte_rev_table' > deftree.c:(.text+0x1e7a0): undefined reference to `byte_rev_table' > deftree.c:(.text+0x1e7b4): undefined reference to `byte_rev_table' > deftree.c:(.text+0x1e7c1): undefined reference to `byte_rev_table' This is really irritating. We save 287 bytes in kernels which don't use bitrev. It isn't worth the hassle, but let's keep plugging. From: Andrew Morton Subject: lib/Kconfig: ZLIB_DEFLATE must select BITREVERSE lib/built-in.o: In function `__bitrev32': deftree.c:(.text+0x1e799): undefined reference to `byte_rev_table' deftree.c:(.text+0x1e7a0): undefined reference to `byte_rev_table' deftree.c:(.text+0x1e7b4): undefined reference to `byte_rev_table' deftree.c:(.text+0x1e7c1): undefined reference to `byte_rev_table' Anything which uses bitrevX() has to select BITREVERSE, to grab lib/bitrev.o. Reported-by: Jim Davis Signed-off-by: Andrew Morton --- lib/Kconfig | 1 + 1 file changed, 1 insertion(+) diff -puN lib/Kconfig~lib-kconfig-zlib_deflate-must-select-bitreverse lib/Kconfig --- a/lib/Kconfig~lib-kconfig-zlib_deflate-must-select-bitreverse +++ a/lib/Kconfig @@ -220,6 +220,7 @@ config ZLIB_INFLATE config ZLIB_DEFLATE tristate + select BITREVERSE config LZO_COMPRESS tristate _