From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A9C12C55186 for ; Wed, 22 Apr 2020 10:07:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5A8D120575 for ; Wed, 22 Apr 2020 10:07:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587550046; bh=9+x2FW9k7r3YtG8FnuuW9O/Ga8X9b8fEaiNci1x3PEc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=SfNSN9inrJ/KpXqqiZcwuSPmyu+oxNT2JVNAQ0gf1zGHV159cH+NlVLuMdyHxCHde qN/AGjiVwCV6cxLDwU9b2mJ6tU9DEQ9pqVm1zsFskKSCYdrP6j2yjFVjYkHDkm/A2i UYhnIsL+x6H0mLTdgw5rMLwJFmIVXkKkgVTionJI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726685AbgDVKHZ (ORCPT ); Wed, 22 Apr 2020 06:07:25 -0400 Received: from mail.kernel.org ([198.145.29.99]:59878 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727941AbgDVKHV (ORCPT ); Wed, 22 Apr 2020 06:07:21 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id D3A3120780; Wed, 22 Apr 2020 10:07:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587550040; bh=9+x2FW9k7r3YtG8FnuuW9O/Ga8X9b8fEaiNci1x3PEc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=QRi1JJ0yUquZ2iXQGg16WNJaOdor6jNFDgJLISbNI/vcuHIU8D45+QBBZE/Oulm2A P3d2KLzShDQIUlGYItDdSGPZSikSUQnDQS033sipbgUeAidKjYyFMOjn+5mNm+9cRo 3WstKQ98eQgQCErkuBIqa0oIzJsSwTRdyw81dnNA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Vegard Nossum , Andrew Morton , Masahiro Yamada , Daniel Santos , Rasmus Villemoes , Ian Abbott , Joe Perches , Linus Torvalds , Sasha Levin Subject: [PATCH 4.9 111/125] compiler.h: fix error in BUILD_BUG_ON() reporting Date: Wed, 22 Apr 2020 11:57:08 +0200 Message-Id: <20200422095050.661714139@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200422095032.909124119@linuxfoundation.org> References: <20200422095032.909124119@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Vegard Nossum [ Upstream commit af9c5d2e3b355854ff0e4acfbfbfadcd5198a349 ] compiletime_assert() uses __LINE__ to create a unique function name. This means that if you have more than one BUILD_BUG_ON() in the same source line (which can happen if they appear e.g. in a macro), then the error message from the compiler might output the wrong condition. For this source file: #include #define macro() \ BUILD_BUG_ON(1); \ BUILD_BUG_ON(0); void foo() { macro(); } gcc would output: ./include/linux/compiler.h:350:38: error: call to `__compiletime_assert_9' declared with attribute error: BUILD_BUG_ON failed: 0 _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__) However, it was not the BUILD_BUG_ON(0) that failed, so it should say 1 instead of 0. With this patch, we use __COUNTER__ instead of __LINE__, so each BUILD_BUG_ON() gets a different function name and the correct condition is printed: ./include/linux/compiler.h:350:38: error: call to `__compiletime_assert_0' declared with attribute error: BUILD_BUG_ON failed: 1 _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__) Signed-off-by: Vegard Nossum Signed-off-by: Andrew Morton Reviewed-by: Masahiro Yamada Reviewed-by: Daniel Santos Cc: Rasmus Villemoes Cc: Ian Abbott Cc: Joe Perches Link: http://lkml.kernel.org/r/20200331112637.25047-1-vegard.nossum@oracle.com Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin --- include/linux/compiler.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/include/linux/compiler.h b/include/linux/compiler.h index 0020ee1cab37a..7837afabbd78e 100644 --- a/include/linux/compiler.h +++ b/include/linux/compiler.h @@ -546,7 +546,7 @@ unsigned long read_word_at_a_time(const void *addr) * compiler has support to do so. */ #define compiletime_assert(condition, msg) \ - _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__) + _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__) #define compiletime_assert_atomic_type(t) \ compiletime_assert(__native_word(t), \ -- 2.20.1