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[2620:137:e000::1:20]) by mx.google.com with ESMTP id x19-20020a1709064bd300b00783d1a13d69si1381859ejv.231.2022.09.30.04.19.41; Fri, 30 Sep 2022 04:20:31 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=aculab.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232207AbiI3LSK convert rfc822-to-8bit (ORCPT + 99 others); Fri, 30 Sep 2022 07:18:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50028 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230042AbiI3LRv (ORCPT ); Fri, 30 Sep 2022 07:17:51 -0400 Received: from eu-smtp-delivery-151.mimecast.com (eu-smtp-delivery-151.mimecast.com [185.58.85.151]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0384317884 for ; Fri, 30 Sep 2022 04:02:44 -0700 (PDT) Received: from AcuMS.aculab.com (156.67.243.121 [156.67.243.121]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384) id uk-mta-304-1kEuWYt-Pb-bGG9NzbX_dA-1; Fri, 30 Sep 2022 12:02:41 +0100 X-MC-Unique: 1kEuWYt-Pb-bGG9NzbX_dA-1 Received: from AcuMS.Aculab.com (10.202.163.6) by AcuMS.aculab.com (10.202.163.6) with Microsoft SMTP Server (TLS) id 15.0.1497.38; Fri, 30 Sep 2022 12:02:38 +0100 Received: from AcuMS.Aculab.com ([::1]) by AcuMS.aculab.com ([::1]) with mapi id 15.00.1497.040; Fri, 30 Sep 2022 12:02:38 +0100 From: David Laight To: 'Hugh Dickins' , Vlastimil Babka CC: Joel Fernandes , Hyeonggon Yoo <42.hyeyoo@gmail.com>, Matthew Wilcox , Andrew Morton , "linux-kernel@vger.kernel.org" , "linux-mm@kvack.org" Subject: RE: amusing SLUB compaction bug when CC_OPTIMIZE_FOR_SIZE Thread-Topic: amusing SLUB compaction bug when CC_OPTIMIZE_FOR_SIZE Thread-Index: AQHY1LmyNvo5HN+EEECxPXiP8YKQXa33zoaA Date: Fri, 30 Sep 2022 11:02:38 +0000 Message-ID: References: <35502bdd-1a78-dea1-6ac3-6ff1bcc073fa@suse.cz> <16fe443a-dabe-aa46-6bc7-dad03f29e0dc@google.com> In-Reply-To: <16fe443a-dabe-aa46-6bc7-dad03f29e0dc@google.com> Accept-Language: en-GB, en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.202.205.107] MIME-Version: 1.0 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: aculab.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00,RCVD_IN_DNSWL_NONE, SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > > > Regarding "conflicting" alignment requests: yes, I agree with you, > > > it would have to be a toolchain bug if when asked to align 2 and to > > > align 4, it chose not to align 4. See https://godbolt.org/z/3nGsTaf5e the align() directive takes precedence. Here you only want to ensure the alignment is at least 4. David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)