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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 1495BC282DD for ; Fri, 24 May 2019 02:12:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C7D1F217F9 for ; Fri, 24 May 2019 02:12:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388479AbfEXCMN (ORCPT ); Thu, 23 May 2019 22:12:13 -0400 Received: from mail.kernel.org ([198.145.29.99]:54502 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727037AbfEXCMN (ORCPT ); Thu, 23 May 2019 22:12:13 -0400 Received: from oasis.local.home (cpe-66-24-58-225.stny.res.rr.com [66.24.58.225]) (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 1D962217D7; Fri, 24 May 2019 02:12:12 +0000 (UTC) Date: Thu, 23 May 2019 22:12:10 -0400 From: Steven Rostedt To: Miguel Ojeda Cc: Ingo Molnar , Linus Torvalds , linux-kernel@vger.kernel.org Subject: Re: [PATCH] tracing: silence GCC 9 array bounds warning Message-ID: <20190523221210.4a2bb326@oasis.local.home> In-Reply-To: <20190523124535.GA12931@gmail.com> References: <20190523124535.GA12931@gmail.com> X-Mailer: Claws Mail 3.17.3 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 23 May 2019 14:45:35 +0200 Miguel Ojeda wrote: > +/* > + * Reset the state of the trace_iterator so that it can read consumed data. > + * Normally, the trace_iterator is used for reading the data when it is not > + * consumed, and must retain state. > + */ > +static __always_inline void trace_iterator_reset(struct trace_iterator *iter) > +{ > + const size_t offset = offsetof(struct trace_iterator, seq); > + > + /* > + * Keep gcc from complaining about overwriting more than just one > + * member in the structure. > + */ > + memset((char *)(iter) + offset, 0, sizeof(struct trace_iterator) - offset); I still prefer the typecast of void *, as that's used a bit more in the kernel, but since char * is also used (not as much), I'll leave it. But the parenthesis around iter are unnecessary. I'll remove them. -- Steve > + > + iter->pos = -1; > +} > +