From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by sourceware.org (Postfix) with ESMTPS id A43343858016 for ; Tue, 15 Feb 2022 10:57:07 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org A43343858016 Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-127-wTmPZC8YOruOiNLUj2wADQ-1; Tue, 15 Feb 2022 05:56:57 -0500 X-MC-Unique: wTmPZC8YOruOiNLUj2wADQ-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 06D60814246; Tue, 15 Feb 2022 10:56:56 +0000 (UTC) Received: from tucnak.zalov.cz (unknown [10.39.192.125]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 55CD95F921; Tue, 15 Feb 2022 10:56:55 +0000 (UTC) Received: from tucnak.zalov.cz (localhost [127.0.0.1]) by tucnak.zalov.cz (8.16.1/8.16.1) with ESMTPS id 21FAuqD81943901 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NOT); Tue, 15 Feb 2022 11:56:52 +0100 Received: (from jakub@localhost) by tucnak.zalov.cz (8.16.1/8.16.1/Submit) id 21FAupTj1943900; Tue, 15 Feb 2022 11:56:51 +0100 Date: Tue, 15 Feb 2022 11:56:51 +0100 From: Jakub Jelinek To: Tobias Burnus Cc: gcc-patches , fortran , "Vollweiler, Marcel" Subject: Re: [Patch] Fortran/OpenMP: Fix depend-clause handling Message-ID: <20220215105651.GO2646553@tucnak> Reply-To: Jakub Jelinek References: <5c942a0f-cc45-1919-af0b-57aa0fff8733@codesourcery.com> MIME-Version: 1.0 In-Reply-To: <5c942a0f-cc45-1919-af0b-57aa0fff8733@codesourcery.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=us-ascii Content-Disposition: inline X-Spam-Status: No, score=-5.2 required=5.0 tests=BAYES_00, DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, RCVD_IN_DNSWL_LOW, SPF_HELO_NONE, SPF_NONE, TXREP, T_SCC_BODY_TEXT_LINE autolearn=unavailable autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on server2.sourceware.org X-BeenThere: fortran@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Fortran mailing list List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 15 Feb 2022 10:57:08 -0000 On Tue, Feb 15, 2022 at 11:26:12AM +0100, Tobias Burnus wrote: > As found by Marcel, the 'depend' clause was differently handled in > 'omp depobj(...) depend(...)' and in 'omp task depend(...)'. > > The problem was that for a scalar pointer, depobj depended > on the pointer address - while task depended on the pointer-target address. > > If one now combines depobj and direct var dependency, the dependency > is on different addresses, such that the dependency is not honored. > Marcel's example is testsuite/libgomp.fortran/depend-4.f90. > (Thanks for the report!) > > > I think in the real world, the problem is not that big as most > code either uses depobj or a variable and does not mix them. Likewise, > using the address of a temporary variable (cf. below) will also usually > work in terms of dependency. > > > The attached patch does: > - depend clause (as used by task etc): > For scalar allocatable/pointer, add another dereference > > - For depobj (which handles the depend clause by itself) > - Fix array(element) handling by coping the depend-clause. > Before the result was 'D.123 = var; depobj = &D.123;' > which is really not intended. > - Several issues related to optional and allocatable/pointer. > > OK for mainline? Does backporting to GCC 11 make sense? Ok. Dunno about backporting, perhaps later. Jakub