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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 4D9EAC76195 for ; Fri, 19 Jul 2019 04:16:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 25E6921882 for ; Fri, 19 Jul 2019 04:16:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1563509786; bh=j5vQegVgi3iwZOVRM1vroQFrzFJwIS+a7HHKZiasCoM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=mu58rqSOPAsKwLmSU6YilPqLIOo6Vj3c2mC0gFK9Ezdm6BE83MZ6+n1YVSjbRGNYB r1RclkdeDeCjcGN4JXu3U1zXB6wJOrA0wZApR+p55emVYLxjFT7QoEUdkIPMMG/v+Y SFW5/BWNZSyM+r2Jx5cvP8cR95X+isyACZW9Wowo= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728130AbfGSEQY (ORCPT ); Fri, 19 Jul 2019 00:16:24 -0400 Received: from mail.kernel.org ([198.145.29.99]:51368 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388970AbfGSEPD (ORCPT ); Fri, 19 Jul 2019 00:15:03 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id AF0BA218B6; Fri, 19 Jul 2019 04:15:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1563509702; bh=j5vQegVgi3iwZOVRM1vroQFrzFJwIS+a7HHKZiasCoM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=kH8ykJEklOCRVl3UXEStP1b9DN6eOgtkIbl6bCHLj5JO/tgXluX2KLhY7SjLcXhnn neq5et3mCV79ZbA4plzwF7BRrkv/lkZvcO+/NRuk924jdM/UkdpsDl5JdO9uRT8pnf xSExHuTqJA/rJVsu9g1VUyei5YyVbyRiwAEnbxXk= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Arnd Bergmann , Nathan Chancellor , Charles Keepax , Lee Jones , Sasha Levin , patches@opensource.cirrus.com, clang-built-linux@googlegroups.com Subject: [PATCH AUTOSEL 4.4 21/35] mfd: arizona: Fix undefined behavior Date: Fri, 19 Jul 2019 00:14:09 -0400 Message-Id: <20190719041423.19322-21-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190719041423.19322-1-sashal@kernel.org> References: <20190719041423.19322-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Arnd Bergmann [ Upstream commit 5da6cbcd2f395981aa9bfc571ace99f1c786c985 ] When the driver is used with a subdevice that is disabled in the kernel configuration, clang gets a little confused about the control flow and fails to notice that n_subdevs is only uninitialized when subdevs is NULL, and we check for that, leading to a false-positive warning: drivers/mfd/arizona-core.c:1423:19: error: variable 'n_subdevs' is uninitialized when used here [-Werror,-Wuninitialized] subdevs, n_subdevs, NULL, 0, NULL); ^~~~~~~~~ drivers/mfd/arizona-core.c:999:15: note: initialize the variable 'n_subdevs' to silence this warning int n_subdevs, ret, i; ^ = 0 Ideally, we would rearrange the code to avoid all those early initializations and have an explicit exit in each disabled case, but it's much easier to chicken out and add one more initialization here to shut up the warning. Signed-off-by: Arnd Bergmann Reviewed-by: Nathan Chancellor Signed-off-by: Charles Keepax Signed-off-by: Lee Jones Signed-off-by: Sasha Levin --- drivers/mfd/arizona-core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/mfd/arizona-core.c b/drivers/mfd/arizona-core.c index d474732cc65c..fb54de5c1aba 100644 --- a/drivers/mfd/arizona-core.c +++ b/drivers/mfd/arizona-core.c @@ -967,7 +967,7 @@ int arizona_dev_init(struct arizona *arizona) unsigned int reg, val, mask; int (*apply_patch)(struct arizona *) = NULL; const struct mfd_cell *subdevs = NULL; - int n_subdevs, ret, i; + int n_subdevs = 0, ret, i; dev_set_drvdata(arizona->dev, arizona); mutex_init(&arizona->clk_lock); -- 2.20.1