From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 100334 invoked by alias); 23 Aug 2017 13:15:48 -0000 Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org Received: (qmail 99091 invoked by uid 89); 23 Aug 2017 13:15:26 -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,RP_MATCHES_RCVD,SPF_HELO_PASS autolearn=ham version=3.3.2 spammy=H*M:b132 X-HELO: mx1.redhat.com Received: from mx1.redhat.com (HELO mx1.redhat.com) (209.132.183.28) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Wed, 23 Aug 2017 13:15:24 +0000 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 879797E454; Wed, 23 Aug 2017 13:15:21 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 879797E454 Authentication-Results: ext-mx03.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx03.extmail.prod.ext.phx2.redhat.com; spf=fail smtp.mailfrom=palves@redhat.com Received: from [127.0.0.1] (ovpn04.gateway.prod.ext.ams2.redhat.com [10.39.146.4]) by smtp.corp.redhat.com (Postfix) with ESMTP id 822217F481; Wed, 23 Aug 2017 13:14:53 +0000 (UTC) Subject: Re: [libcc1] Improve detection of triplet on compiler names To: Sergio Durigan Junior References: <87mv6qhq9u.fsf@redhat.com> <74900a91-685b-2bdc-6cb7-8333ce9c5d0a@redhat.com> <87a82qh1pn.fsf@redhat.com> Cc: GDB Patches , GCC Patches , Tom Tromey , Keith Seitz , Phil Muldoon , Alexandre Oliva From: Pedro Alves Message-ID: Date: Wed, 23 Aug 2017 13:15:00 -0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.4.0 MIME-Version: 1.0 In-Reply-To: <87a82qh1pn.fsf@redhat.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit X-SW-Source: 2017-08/txt/msg00441.txt.bz2 On 08/23/2017 02:07 PM, Sergio Durigan Junior wrote: > On Wednesday, August 23 2017, Pedro Alves wrote: > >> On 08/23/2017 05:17 AM, Sergio Durigan Junior wrote: >>> The GCC patch improves the libcc1::compiler_triplet_regexp::find and >>> libcp1::compiler_triplet_regexp::find methods by first trying to match >>> the triplet in the compiler name and correctly discarding the triplet >>> part of the regexp if the matching succeeds. I've had to do a few >>> modifications on the way the regexp's are built, but I'll explain them >>> in the patch itself. >>> >>> The GDB patch is very simple: it adds the trailing "-" in the triplet >>> regexp. Therefore, we will have a regexp that truly matches the full >>> triplet (e.g., "^(x86_64|i.86)(-[^-]*)?-linux(-gnu)?-") instead of one >>> that leaves the trailing "-" match to libcc1. >>> >>> I've tested this patch both on my Fedora and my Debian machines, and >>> both now work as expected, independently of the presence of the triplet >>> string in the compiler name. I am sorry about the cross-post, but these >>> patches are really dependent on one another. >> >> Is there a backward/forward compatibility impact? > > Unfortunately, yes. > >> Does new GDB work with old GCC? > > No. On Fedora systems, you would get: > > Could not find a compiler matching "^(x86_64|i.86)(-[^-]*)?-linux(-gnu)?--gcc$" > That's a problem then. Please read this: https://sourceware.org/gdb/wiki/GCCCompileAndExecute#How_to_extend_the_gdb.2BAC8-gcc_interface > As can be seen, these failures are now happening because of the trailing > dash that is now included in the triplet regexp by GDB. I don't know if > that warrants a change in the API, though. Thanks, Pedro Alves