From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 118777 invoked by alias); 11 Jul 2017 18:13:11 -0000 Mailing-List: contact fortran-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Post: List-Help: , Sender: fortran-owner@gcc.gnu.org Received: (qmail 118702 invoked by uid 89); 11 Jul 2017 18:13:10 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-7.2 required=5.0 tests=AWL,BAYES_00,GIT_PATCH_2,RCVD_IN_DNSWL_LOW,RP_MATCHES_RCVD,SPF_PASS autolearn=ham version=3.3.2 spammy= X-Spam-User: qpsmtpd, 2 recipients X-HELO: cc-smtpout1.netcologne.de Received: from cc-smtpout1.netcologne.de (HELO cc-smtpout1.netcologne.de) (89.1.8.211) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Tue, 11 Jul 2017 18:13:08 +0000 Received: from cc-smtpin1.netcologne.de (cc-smtpin1.netcologne.de [89.1.8.201]) by cc-smtpout1.netcologne.de (Postfix) with ESMTP id D583C13307; Tue, 11 Jul 2017 20:13:04 +0200 (CEST) Received: from localhost (localhost [127.0.0.1]) by cc-smtpin1.netcologne.de (Postfix) with ESMTP id D14C411DF3; Tue, 11 Jul 2017 20:13:04 +0200 (CEST) Received: from [78.35.144.8] (helo=cc-smtpin1.netcologne.de) by localhost with ESMTP (eXpurgate 4.1.9) (envelope-from ) id 59651530-021e-7f0000012729-7f000001af5c-1 for ; Tue, 11 Jul 2017 20:13:04 +0200 Received: from [192.168.178.20] (xdsl-78-35-144-8.netcologne.de [78.35.144.8]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by cc-smtpin1.netcologne.de (Postfix) with ESMTPSA; Tue, 11 Jul 2017 20:12:59 +0200 (CEST) Subject: Re: [Patch, fortran] PR34640 - ICE when assigning item of a derived-component to a pointer To: Jerry DeLisle , Paul Richard Thomas Cc: "fortran@gcc.gnu.org" , gcc-patches , Damian Rouson , "Bader, Reinhold" References: <36a479a8-e22b-f675-7f3d-b7324f872357@netcologne.de> <3db0f7be-b48b-cbd5-c526-7b29c25437d3@charter.net> From: Thomas Koenig Message-ID: Date: Tue, 11 Jul 2017 18:13:00 -0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.2.1 MIME-Version: 1.0 In-Reply-To: <3db0f7be-b48b-cbd5-c526-7b29c25437d3@charter.net> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit X-SW-Source: 2017-07/txt/msg00030.txt.bz2 Am 11.07.2017 um 16:48 schrieb Jerry DeLisle: > Somewhere in the threads on this, there was mentioned ABI breakage/change. That was me. > Does it really do this? Yes. Look at this part: Index: libgfortran/libgfortran.h =================================================================== *** libgfortran/libgfortran.h (revision 250082) --- libgfortran/libgfortran.h (working copy) *************** struct {\ *** 339,344 **** --- 339,345 ---- type *base_addr;\ size_t offset;\ index_type dtype;\ + index_type span;\ descriptor_dimension dim[r];\ } > If the significant change is in the descriptor and you > just added the span on the end of the structure, I am not convinced this is an > issue. (I have not studied the patch at all, I would rather not bump library > version) Unless I am mistaken, we only build the required dimensions for an array descriptor. Putting it on the end would not work unless we changed that behavior. But we are doing something wrong with the array descriptors anyway. See https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68649#c7 for a description. Other comments in the same PR have some suggestions, but nothing that works (or so I think). So, if we do break the ABI, we could try to fix the remaining issues with the array descriptors - not with this patch, but before 8.1 is released. Flexible array members come to mind. Regards Thomas