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=-0.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED autolearn=no 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 A6646C43331 for ; Wed, 1 Apr 2020 22:58:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6CE5420719 for ; Wed, 1 Apr 2020 22:58:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1585781913; bh=Kh5mNuBzVwAUptRbGYaW4hwn1mM92cXaa8ZH4GIqyjI=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=HfyqBm9Z1xN7GXZUcsRPWZHnNCSdbmb0RlqikVudUrh5jMVyk3Fivj3XtygpexuEM wGqNYKcKTWuFdLlHj6+RzsZTHsCKPsNJ0OOH2QKZrjivUYyqJ+Mq3U5h814UZlSY7n L5z1Ye7ESueEDlvz2d2cnvhycAPU/YqIqAH87s/4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732669AbgDAW6c (ORCPT ); Wed, 1 Apr 2020 18:58:32 -0400 Received: from mail.kernel.org ([198.145.29.99]:56520 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732537AbgDAW6c (ORCPT ); Wed, 1 Apr 2020 18:58:32 -0400 Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (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 C90F6206E9; Wed, 1 Apr 2020 22:58:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1585781912; bh=Kh5mNuBzVwAUptRbGYaW4hwn1mM92cXaa8ZH4GIqyjI=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=mOb+cGJ7ozCiEGTcffpZLjjIhX/YfB87UB79kLOqNXD9sin9Cz/8lhnY3QO1BzwYm NtfIJodLgwn/VC52YbQgVigMxgejaxGtrf9PvJcN268SqE31KE/lmPnnklVAlHdxZe 6FhtA2DePSOteTR8L+1/YbllmSydqyteDpGR0FH8= Date: Wed, 1 Apr 2020 15:58:31 -0700 From: Andrew Morton To: Stephen Rothwell Cc: Linux Next Mailing List , Linux Kernel Mailing List , Longpeng , Jason Gunthorpe , Mike Kravetz , Jason Gunthorpe , Matthew Wilcox , Sean Christopherson Subject: Re: linux-next: build warning after merge of the akpm-current tree Message-Id: <20200401155831.24aa79ebbb14c654a2bee8c0@linux-foundation.org> In-Reply-To: <20200331195612.64c06485@canb.auug.org.au> References: <20200331195612.64c06485@canb.auug.org.au> X-Mailer: Sylpheed 3.5.1 (GTK+ 2.24.31; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-next-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-next@vger.kernel.org On Tue, 31 Mar 2020 19:56:12 +1100 Stephen Rothwell wrote: > Hi all, > > After merging the akpm-current tree, today's linux-next build (i386 > defconfig) produced this warning: > > mm/hugetlb.c: In function 'huge_pte_offset': > cc1: warning: function may return address of local variable [-Wreturn-local-addr] > mm/hugetlb.c:5361:14: note: declared here > 5361 | pud_t *pud, pud_entry; > | ^~~~~~~~~ > cc1: warning: function may return address of local variable [-Wreturn-local-addr] > mm/hugetlb.c:5360:14: note: declared here > 5360 | p4d_t *p4d, p4d_entry; > | ^~~~~~~~~ > > Introduced by commit > > 826ddc88e2cf ("mm/hugetlb: fix a addressing exception caused by huge_pte_offset") I can reproduce this (i386 defconfig, gcc-7.2.0). I can see no way in which this makes any sense. Hopefully it's a gcc bug but it's hard to see how it could have messed up this fairly simple code.