From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753415AbeDIQS1 (ORCPT ); Mon, 9 Apr 2018 12:18:27 -0400 Received: from mail-wr0-f196.google.com ([209.85.128.196]:44236 "EHLO mail-wr0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753231AbeDIQSV (ORCPT ); Mon, 9 Apr 2018 12:18:21 -0400 X-Google-Smtp-Source: AIpwx4/FybrSrFNjPbFDmbk3XdDP4YxHoiVe277Gz2ANWocymB2Vig7FxacMkCgdHjoMwAd/Q+oQ7g== Date: Mon, 9 Apr 2018 18:18:17 +0200 From: Ingo Molnar To: Arnd Bergmann Cc: Frederic Weisbecker , Thomas Gleixner , Peter Zijlstra , "Rafael J. Wysocki" , "Paul E. McKenney" , linux-kernel@vger.kernel.org Subject: Re: [PATCH] tick-sched: avoid a maybe-uninitialized warning Message-ID: <20180409161817.bnmokplnoagyxwrc@gmail.com> References: <20180409122339.1709840-1-arnd@arndb.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180409122339.1709840-1-arnd@arndb.de> User-Agent: NeoMutt/20170609 (1.8.3) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Arnd Bergmann wrote: > The use of bitfields seems to confuse gcc, leading to a false-positive > warning in all compiler versions: > > kernel/time/tick-sched.c: In function 'tick_nohz_idle_exit': > kernel/time/tick-sched.c:538:2: error: 'now' may be used uninitialized in this function [-Werror=maybe-uninitialized] > > This introduces a temporary variable to track the flags so gcc > doesn't have to evaluate twice, eliminating the code path that > leads to the warning. > > Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85301 > Fixes: 1cae544d42d2 ("nohz: Gather tick_sched booleans under a common flag field") > Signed-off-by: Arnd Bergmann Which tree is this against? There's no such commit either in -tip, upstream or in -next AFAICS. Thanks, Ingo