From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 61449 invoked by alias); 24 Nov 2015 13:07:11 -0000 Mailing-List: contact gdb-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-owner@sourceware.org Received: (qmail 60751 invoked by uid 89); 24 Nov 2015 13:07:10 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-2.1 required=5.0 tests=AWL,BAYES_00,RP_MATCHES_RCVD,SPF_HELO_PASS autolearn=ham version=3.3.2 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 (AES256-GCM-SHA384 encrypted) ESMTPS; Tue, 24 Nov 2015 13:07:09 +0000 Received: from int-mx11.intmail.prod.int.phx2.redhat.com (int-mx11.intmail.prod.int.phx2.redhat.com [10.5.11.24]) by mx1.redhat.com (Postfix) with ESMTPS id 79293C0F1CF4 for ; Tue, 24 Nov 2015 13:07:08 +0000 (UTC) Received: from [127.0.0.1] (ovpn01.gateway.prod.ext.ams2.redhat.com [10.39.146.11]) by int-mx11.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id tAOD775M019829 for ; Tue, 24 Nov 2015 08:07:07 -0500 Message-ID: <565460FB.6070103@redhat.com> Date: Tue, 24 Nov 2015 13:07:00 -0000 From: Pedro Alves User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.7.0 MIME-Version: 1.0 To: "gdb@sourceware.org" Subject: C++ conversion status update Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-SW-Source: 2015-11/txt/msg00035.txt.bz2 Hi all, [Project page here: https://sourceware.org/gdb/wiki/cxx-conversion] Good news, we've reached a significant milestone on the C++ conversion -- on a few important hosts, GDB now builds cleanly as a C++ program with no hacks. These are at least: - Aarch64 GNU/Linux - ARM GNU/Linux - x86 GNU/Linux - x86_64 GNU/Linux - x86_64 Mingw-w64 In addition, the testsuite shows no regressions in C++ mode, compared to C mode. Up until recently, we were still using g++'s -fpermissive switch as a shortcut. That allowed deferring fixing a huge number boring cast and enum conversion issues. Most of those issues are now fixed, and since the hosts above cover most of the common, non-host-specific code, we changed the build system to no longer use g++'s -fpermissive switch, and at the same time, made C++ mode default to build with -Werror too, just like C mode. Big thanks goes to Simon Marchi, Yao Qi and others for all the help. There's still a lot of work ahead though. Until all supported hosts can build with a C++ compiler, we'll have to keep supporting building GDB as a C program as well. It's not sufficient to say "builds cleanly on GNU/Linux", because each architecture+OS combination (ARM GNU/Linux, x86 Windows, etc.) has it's own set of native debugger support files (the *-nat.c files) that are not built on any other host. The plan I propose next is to default to building in C++ mode on hosts that are known to build cleanly in C++ mode. Or rather, change the default to be C++ mode, _except_ for hosts/ports that haven't been converted yet. Then, as ports get converted, one by one they'll be removed from the "can't do C++ yet" list. That gives us a defined stopping point -- when the list becomes empty, and after a reasonable period, we can decide to remove support for building in C mode and start making use of C++ features. The question I have is which hosts (Architecture + OS combination) people care about that still need C++ conversion work and thus should be on that list? This is where anyone can help! I've created the "users/palves/cxx-conversion" branch (on sourceware.org) where I committed a patch that implements the list idea. I filled in a set of hosts that I _thought_ wouldn't build, but I don't really know for sure. So I'd like to invite people to try to build master on their favorite host with --enable-build-with-cxx, and report back the result. Thanks, Pedro Alves