From patchwork Tue Feb 11 21:06:18 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Gustavo A. R. Silva" X-Patchwork-Id: 207315 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=-13.1 required=3.0 tests=DKIM_INVALID, DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_SANE_1 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 980A1C35242 for ; Tue, 11 Feb 2020 21:24:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7044E20659 for ; Tue, 11 Feb 2020 21:24:17 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=embeddedor.com header.i=@embeddedor.com header.b="NVUjzx89" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727573AbgBKVYQ (ORCPT ); Tue, 11 Feb 2020 16:24:16 -0500 Received: from gateway36.websitewelcome.com ([192.185.188.18]:41595 "EHLO gateway36.websitewelcome.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726968AbgBKVYQ (ORCPT ); Tue, 11 Feb 2020 16:24:16 -0500 X-Greylist: delayed 1230 seconds by postgrey-1.27 at vger.kernel.org; Tue, 11 Feb 2020 16:24:15 EST Received: from cm12.websitewelcome.com (cm12.websitewelcome.com [100.42.49.8]) by gateway36.websitewelcome.com (Postfix) with ESMTP id 91DE2414FE1AD for ; Tue, 11 Feb 2020 14:17:45 -0600 (CST) Received: from gator4166.hostgator.com ([108.167.133.22]) by cmsmtp with SMTP id 1ch7jHoD5vBMd1ch7jbPwB; Tue, 11 Feb 2020 15:03:45 -0600 X-Authority-Reason: nr=8 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=embeddedor.com; s=default; h=Content-Type:MIME-Version:Message-ID:Subject: Cc:To:From:Date:Sender:Reply-To:Content-Transfer-Encoding:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:In-Reply-To:References:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=Y7FMQ3aFcSbTB8cXSN/10Y25Q6I9Sqxro0ixjLvyexk=; b=NVUjzx89ff02Y0550Cc9HR4fAV y8xgLLMBqHAJcRuoYH/4vdjQlwmneVydHsfxguYwcJemWBAIPTaH5ACThZNw/j9YPPszQTd3icsx7 U+v8QkoMqssJf+0DLG7bz90E+KHjnEEjbCAcF7/fMJV0CS+I9YjRTsjTeSau8ZIvWL0QO5RZmkBH5 Mo9HA971WK+zi4licGrT47AWMX8GavgfO5a7EaL3XONr0IgFVBS2Fx+Bnk5oVh9pOOh52jbY5YMpW bY4JaEdAmrd6n3YBDyb0tJMBYkMJS4rHr6EFQLvL5BVmnVdN9WDD5iCxqHzkn+aXLokWXCTaEqr5U VKHDlH5A==; Received: from [200.68.140.36] (port=15247 helo=embeddedor) by gator4166.hostgator.com with esmtpa (Exim 4.92) (envelope-from ) id 1j1ch5-0026gU-VR; Tue, 11 Feb 2020 15:03:44 -0600 Date: Tue, 11 Feb 2020 15:06:18 -0600 From: "Gustavo A. R. Silva" To: Linus Walleij , Bartosz Golaszewski , Masahiro Yamada Cc: linux-gpio@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" Subject: [PATCH] gpio: uniphier: Replace zero-length array with flexible-array member Message-ID: <20200211210618.GA29823@embeddedor> MIME-Version: 1.0 Content-Disposition: inline User-Agent: Mutt/1.9.4 (2018-02-28) X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - gator4166.hostgator.com X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - embeddedor.com X-BWhitelist: no X-Source-IP: 200.68.140.36 X-Source-L: No X-Exim-ID: 1j1ch5-0026gU-VR X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: (embeddedor) [200.68.140.36]:15247 X-Source-Auth: gustavo@embeddedor.com X-Email-Count: 9 X-Source-Cap: Z3V6aWRpbmU7Z3V6aWRpbmU7Z2F0b3I0MTY2Lmhvc3RnYXRvci5jb20= X-Local-Domain: yes Sender: linux-gpio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-gpio@vger.kernel.org The current codebase makes use of the zero-length array language extension to the C90 standard, but the preferred mechanism to declare variable-length types such as these ones is a flexible array member[1][2], introduced in C99: struct foo { int stuff; struct boo array[]; }; By making use of the mechanism above, we will get a compiler warning in case the flexible array does not occur last in the structure, which will help us prevent some kind of undefined behavior bugs from being inadvertenly introduced[3] to the codebase from now on. This issue was found with the help of Coccinelle. [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html [2] https://github.com/KSPP/linux/issues/21 [3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour") Signed-off-by: Gustavo A. R. Silva --- drivers/gpio/gpio-uniphier.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpio/gpio-uniphier.c b/drivers/gpio/gpio-uniphier.c index 0f662b297a95..9843638d99d0 100644 --- a/drivers/gpio/gpio-uniphier.c +++ b/drivers/gpio/gpio-uniphier.c @@ -33,7 +33,7 @@ struct uniphier_gpio_priv { struct irq_domain *domain; void __iomem *regs; spinlock_t lock; - u32 saved_vals[0]; + u32 saved_vals[]; }; static unsigned int uniphier_gpio_bank_to_reg(unsigned int bank)