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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 5473FC5475B for ; Wed, 6 Mar 2024 19:40:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=aJQbdgZKjt3hC5Lxf1ZMX53czAKc6KU0YHiAPB7jJT8=; b=uv7COfsJ78/UA8TvAxzvtjQAJG fW/LJDL9iaicrj04jP2PryKNXICdDXMmbSjQQiH6uvN38e+v/iyQNC1/GBk6cwXkXWg0yPARiSkcS JTUv5+m9C/ECEN3fIDKCF/yU/LjGcHTVeOvOQlK/sbLM0sfmVKoIv5Zc8ejZS8F4S/IXTRIKcW+1p bb6RlOLCtPNCyeu0IIEFfyp0POLo5xrB1nNFS2TYM6IT+Lz4i2PezuJtTuenr1D0YoVk8Bqro8AMX dpO00TVjzADI2sNXFxGWN6r7QlfJAACp4C1Wr5heR4/ryKtf+OgJyK0uDIhRqoLPucRud6uIu4Y21 xdj9sFFA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1rhx7s-00000001ezo-1Lqx; Wed, 06 Mar 2024 19:40:28 +0000 Received: from dfw.source.kernel.org ([139.178.84.217]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1rhx7o-00000001exG-0z0f; Wed, 06 Mar 2024 19:40:26 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id 9DC8761A15; Wed, 6 Mar 2024 19:40:23 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A15D6C433C7; Wed, 6 Mar 2024 19:40:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1709754023; bh=5/Zn7NHW1uTwkwELhBiHm6Z/dCQjigrm4gBqAaJY9Ho=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=JKLC432oMy/qlvpf9vVwvVrMXSu9agkHKeeO3zV41CO6dZ20Sm+V1eNXj22cNLo5Z G+5sWuR3L6AmhazuPitHyEI9Q62kI8Foz0g935QQYo5vAzrjZ8nDxoXm0R/Wr/9CFG vPXG+0e+XKAtpxEOR49vSMOYzsg0x7aSvwcfzAYphXrOpC1eDjwtgQjdyTDVvoqQSC SuqdIW6aNwut2F9YETPd7sXXRv9mmM45omYm/5wkTilQZD9GK9SEX1YNN/R2vmh6sP W8ymyxZAaL1dbgbc4v+T12pja5MoSTS/EQylltQZ+i5r84F3qO2rQpqaPUmf0jdR02 kkHwk+XGSsg9Q== Date: Wed, 6 Mar 2024 12:40:20 -0700 From: Nathan Chancellor To: Chunhui Li Cc: Petr Mladek , Steven Rostedt , John Ogness , Sergey Senozhatsky , Matthias Brugger , AngeloGioacchino Del Regno , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, wsd_upstream@mediatek.com Subject: Re: [PATCH] printk: fix _entry_ptr build warning Message-ID: <20240306194020.GA3711543@dev-arch.thelio-3990X> References: <20240306092647.16010-1-chunhui.li@mediatek.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240306092647.16010-1-chunhui.li@mediatek.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240306_114024_416440_AF5F6E6F X-CRM114-Status: GOOD ( 20.02 ) X-BeenThere: linux-mediatek@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-mediatek" Errors-To: linux-mediatek-bounces+linux-mediatek=archiver.kernel.org@lists.infradead.org On Wed, Mar 06, 2024 at 05:26:47PM +0800, Chunhui Li wrote: > We build with Werror and suffer build error when > enable CONFIG_PRINTK_INDEX, such as > gfp.h:223:2: error: unused variable '_entry_ptr' > ratelimit.h:31:3: error: unused variable '_entry_ptr' > kallsyms.h:172:2: error: unused variable '_entry_ptr' > [-Werror,-Wunused-variable] > > Fix the warning by appending __attribute__((unused)). > > Signed-off-by: Chunhui Li Are these warnings being emitted from an Android version of clang, specifically 18.0.0 with the build ID of 11209041 (you should be able to tell this from the "bid" field in the BUILD_INFO file in the clang toolchain folder)? This seems remarkably similar to https://github.com/ClangBuiltLinux/linux/issues/1977, which was a report using that version of Android clang. Ultimately, this warning is a bug in a clang change that was quickly found and reverted upstream https://github.com/llvm/llvm-project/commit/f0f395e00e2ec3f1f20ca9021d1554fde73d56c9 https://github.com/llvm/llvm-project/commit/cfa578cde0314935c6eb5d7fa19ec26390d431dd but unfortunately, Android picked a revision for the 11209041 build that was between the landing of the broken commit and its revert. It was quickly fixed with the 11368308 build https://android.googlesource.com/platform/prebuilts/clang/host/linux-x86/+/42d100b025eb5f4a41781348016c148e9e912cf9 so you should just be able to update to that version to resolve this. Cheers, Nathan > --- > include/linux/printk.h | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/include/linux/printk.h b/include/linux/printk.h > index 8ef499ab3c1e..749c1c4257f1 100644 > --- a/include/linux/printk.h > +++ b/include/linux/printk.h > @@ -392,7 +392,7 @@ struct pi_entry { > .level = __builtin_constant_p(_level) ? (_level) : NULL, \ > .subsys_fmt_prefix = _subsys_fmt_prefix,\ > }; \ > - static const struct pi_entry *_entry_ptr \ > + static const struct pi_entry *_entry_ptr __attribute__((unused)) \ > __used __section(".printk_index") = &_entry; \ > } \ > } while (0) > -- > 2.18.0 > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel