From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932587Ab2GXVIY (ORCPT ); Tue, 24 Jul 2012 17:08:24 -0400 Received: from blu0-omc2-s28.blu0.hotmail.com ([65.55.111.103]:52731 "EHLO blu0-omc2-s28.blu0.hotmail.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755638Ab2GXVIW (ORCPT ); Tue, 24 Jul 2012 17:08:22 -0400 X-Originating-IP: [174.92.93.236] X-Originating-Email: [dave.anglin@bell.net] Message-ID: From: John David Anglin To: Fengguang Wu In-Reply-To: <20120724074844.GA9519@localhost> Subject: Re: [next:akpm 129/309] net/core/sock.c:274:36: error: initializer element is not constant References: <20120722163058.GB13376@localhost> <20120723111619.GT9222@suse.de> <1343042420.3027.11.camel@dabdike.int.hansenpartnership.com> <20120723114258.GV9222@suse.de> <20120723122905.GA22476@localhost> <20120724074844.GA9519@localhost> Content-Type: text/plain; charset="US-ASCII"; format=flowed; delsp=yes Content-Transfer-Encoding: 7bit MIME-Version: 1.0 (Apple Message framework v936) Date: Tue, 24 Jul 2012 17:08:04 -0400 CC: Mel Gorman , James Bottomley , kernel-janitors@vger.kernel.org, Kyle McMartin , Andrew Morton , LKML , Parisc List X-Mailer: Apple Mail (2.936) X-OriginalArrivalTime: 24 Jul 2012 21:08:20.0631 (UTC) FILETIME=[742D0270:01CD69E0] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 24-Jul-12, at 3:48 AM, Fengguang Wu wrote: > Here is the line in sock.i: > > struct static_key memalloc_socks = ((struct static_key) { .enabled = > ((atomic_t) { (0) }) }); The above line contains two compound literals. It also uses a designated initializer to initialize the field enabled. A compound literal is not a constant expression. The location of the above statement isn't fully clear, but if a compound literal occurs outside the body of a function, the initializer list must consist of constant expressions. Removing "(atomic_t)" from the define results in a constant expression. Test case: typedef struct { long enabled; } atomic_t; struct static_key { atomic_t enabled; int x; }; struct static_key memalloc_socks = ((struct static_key) { .enabled = ((atomic_t) { (0) }) }); Dave -- John David Anglin dave.anglin@bell.net