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 79ADBC76188 for ; Fri, 19 Jul 2019 04:18:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4EE092084C for ; Fri, 19 Jul 2019 04:18:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1563509890; bh=8ZI5KHIikTg8AUBhIZ0V00NlYlYYAULFOpP7aV3KTBM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=GWPfnzQNlHQYYyyRH1cg+355Vj6O0MARrgxevUWOpqjbq0T8kmb1avKvpAWYnLmdh 41pH1e3onS8CYX5FL/Nk4SaNTJ8vXaPUvGQ831vLyIrX9HCISvgq1/xL5wgVgHjfnW ftmAiX5KnuGrPvE683wM5OhiE89BZFnCAona75IY= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389421AbfGSENw (ORCPT ); Fri, 19 Jul 2019 00:13:52 -0400 Received: from mail.kernel.org ([198.145.29.99]:49878 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389375AbfGSENt (ORCPT ); Fri, 19 Jul 2019 00:13:49 -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 25FFD21872; Fri, 19 Jul 2019 04:13:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1563509628; bh=8ZI5KHIikTg8AUBhIZ0V00NlYlYYAULFOpP7aV3KTBM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=FjqbAk0hy+qlG+8lFQEs4ZstNV1Km+Ne5Yyp0ehWeRFjZhndW5jl49wl6tz74f2l0 qCa6K3pZ6uQOwKA94IEml8Y4eh9h5V6vUNNoZltDuGzKOar9bf7uykRoIgxNuonVoz b15enSRALng9sLzAa0NPPRZJMgUh2M3BM/U88Kro= 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 4.9 26/45] mfd: arizona: Fix undefined behavior Date: Fri, 19 Jul 2019 00:12:45 -0400 Message-Id: <20190719041304.18849-26-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190719041304.18849-1-sashal@kernel.org> References: <20190719041304.18849-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@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 41767f7239bb..0556a9749dbe 100644 --- a/drivers/mfd/arizona-core.c +++ b/drivers/mfd/arizona-core.c @@ -1038,7 +1038,7 @@ 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