From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 100937 invoked by alias); 15 Jun 2017 17:51:05 -0000 Mailing-List: contact gcc-patches-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-patches-owner@gcc.gnu.org Received: (qmail 100917 invoked by uid 89); 15 Jun 2017 17:51:05 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-1.9 required=5.0 tests=BAYES_00,RCVD_IN_DNSWL_NONE,SPF_HELO_PASS,SPF_PASS autolearn=ham version=3.3.2 spammy= X-HELO: EUR01-VE1-obe.outbound.protection.outlook.com Received: from mail-ve1eur01on0042.outbound.protection.outlook.com (HELO EUR01-VE1-obe.outbound.protection.outlook.com) (104.47.1.42) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Thu, 15 Jun 2017 17:51:03 +0000 Received: from AM5PR0802MB2610.eurprd08.prod.outlook.com (10.175.46.18) by AM5PR0802MB2386.eurprd08.prod.outlook.com (10.175.43.148) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1178.14; Thu, 15 Jun 2017 17:51:04 +0000 Received: from AM5PR0802MB2610.eurprd08.prod.outlook.com ([fe80::611d:6946:9597:da06]) by AM5PR0802MB2610.eurprd08.prod.outlook.com ([fe80::611d:6946:9597:da06%17]) with mapi id 15.01.1178.013; Thu, 15 Jun 2017 17:51:04 +0000 From: Wilco Dijkstra To: Richard Earnshaw , James Greenhalgh CC: GCC Patches , nd , Marcus Shawcroft Subject: Re: [PATCH v3][AArch64] Fix symbol offset limit Date: Thu, 15 Jun 2017 17:51:00 -0000 Message-ID: References: <896d038e-f19f-d95e-2213-f3360ba71b28@arm.com> <20170614140702.GB8010@arm.com> <31845e36-14f3-eb1e-ef11-5bcf70a11b15@arm.com> , In-Reply-To: authentication-results: gcc.gnu.org; dkim=none (message not signed) header.d=none;gcc.gnu.org; dmarc=none action=none header.from=arm.com; x-ms-publictraffictype: Email x-microsoft-exchange-diagnostics: 1;AM5PR0802MB2386;7:YUfivys8HsyUAKwwGP4/+BBozbL99SXuVyZbSdGtVgnjfPYcxZvOH9rX9rrbzZ2ecIFZe2LPEsh1s3NbiumAMo+8NqmTFKexDxJMPkvDpYVv+pl7rz3sCpPPFMi1qyrcBfZFpUEe1xkUzEscd1QgeU6922YBBga1u5VdWxieQPIGN9lh4BegQTW9jZVNMZS84wGR9uYdFnfLRmRreui6IDYuYW+E167Uyr1qyf+V1ZvrtXU9XAlQDyX+Arnu8b/kNYG4Qv0aj3lafh/CD3Qy/YuRh+bbO1wXwBzlShkr7dCUTFoH/l53sRFM6lHqlSa0TtZ4OB3uopq8HhCmLvjZ+w== x-ms-office365-filtering-correlation-id: 69874c85-db46-4176-85d3-08d4b4171827 x-ms-office365-filtering-ht: Tenant x-microsoft-antispam: UriScan:;BCL:0;PCL:0;RULEID:(22001)(2017030254075)(48565401081)(201703131423075)(201703031133081)(201702281549075);SRVR:AM5PR0802MB2386; x-ms-traffictypediagnostic: AM5PR0802MB2386: nodisclaimer: True x-microsoft-antispam-prvs: x-exchange-antispam-report-test: UriScan:; x-exchange-antispam-report-cfa-test: BCL:0;PCL:0;RULEID:(100000700101)(100105000095)(100000701101)(100105300095)(100000702101)(100105100095)(6040450)(601004)(2401047)(8121501046)(5005006)(93006095)(93001095)(3002001)(10201501046)(100000703101)(100105400095)(6055026)(6041248)(20161123555025)(20161123558100)(20161123564025)(20161123560025)(20161123562025)(201703131423075)(201702281528075)(201703061421075)(201703061406153)(6072148)(100000704101)(100105200095)(100000705101)(100105500095);SRVR:AM5PR0802MB2386;BCL:0;PCL:0;RULEID:(100000800101)(100110000095)(100000801101)(100110300095)(100000802101)(100110100095)(100000803101)(100110400095)(100000804101)(100110200095)(100000805101)(100110500095);SRVR:AM5PR0802MB2386; x-forefront-prvs: 0339F89554 x-forefront-antispam-report: SFV:NSPM;SFS:(10009020)(6009001)(39400400002)(39410400002)(39850400002)(39450400003)(39840400002)(39860400002)(24454002)(81166006)(7696004)(76176999)(305945005)(54356999)(6116002)(50986999)(102836003)(93886004)(74316002)(6506006)(86362001)(2900100001)(5660300001)(3280700002)(8676002)(8936002)(6436002)(25786009)(3660700001)(478600001)(72206003)(5250100002)(9686003)(2950100002)(6636002)(14454004)(7736002)(33656002)(54906002)(99286003)(229853002)(4326008)(6246003)(53936002)(55016002)(38730400002)(189998001)(2906002);DIR:OUT;SFP:1101;SCL:1;SRVR:AM5PR0802MB2386;H:AM5PR0802MB2610.eurprd08.prod.outlook.com;FPR:;SPF:None;MLV:sfv;LANG:en; spamdiagnosticoutput: 1:99 spamdiagnosticmetadata: NSPM Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-OriginatorOrg: arm.com X-MS-Exchange-CrossTenant-originalarrivaltime: 15 Jun 2017 17:51:04.7635 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: f34e5979-57d9-4aaa-ad4d-b122a662184d X-MS-Exchange-Transport-CrossTenantHeadersStamped: AM5PR0802MB2386 X-SW-Source: 2017-06/txt/msg01139.txt.bz2 Richard Earnshaw wrote: > > You can write it, but it's meaningless by the C standard.=A0 You can't > take the address beyond one after the size of the object, so anything > more than &a+1 has no meaning. No it's perfectly valid and such out-of-range cases occur thousands of times when building any non-trivial code. For example a[i + C] transforms into (&a + C)[i]. Wilco =20=20=20=20