From owner-freebsd-stable@FreeBSD.ORG Wed Sep 19 18:13:51 2012 Return-Path: Delivered-To: freebsd-stable@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id B54AF106566B; Wed, 19 Sep 2012 18:13:51 +0000 (UTC) (envelope-from gpalmer@freebsd.org) Received: from noop.in-addr.com (mail.in-addr.com [IPv6:2001:470:8:162::1]) by mx1.freebsd.org (Postfix) with ESMTP id 7F4228FC12; Wed, 19 Sep 2012 18:13:51 +0000 (UTC) Received: from gjp by noop.in-addr.com with local (Exim 4.80 (FreeBSD)) (envelope-from ) id 1TEOmL-0002hN-TO; Wed, 19 Sep 2012 14:13:41 -0400 Date: Wed, 19 Sep 2012 14:13:41 -0400 From: Gary Palmer To: Roland Smith Message-ID: <20120919181341.GD77784@in-addr.com> References: <20120912060420.GE31029@lonesome.com> <20120917194317.GB43284@slackbox.erewhon.net> <50579DEC.3060902@FreeBSD.org> <20120919171250.GA50969@slackbox.erewhon.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20120919171250.GA50969@slackbox.erewhon.net> X-SA-Exim-Connect-IP: X-SA-Exim-Mail-From: gpalmer@freebsd.org X-SA-Exim-Scanned: No (on noop.in-addr.com); SAEximRunCond expanded to false Cc: Mark Linimon , Dimitry Andric , Andreas Nilsson , FreeBSD Stable Mailing List Subject: Re: Clang as default compiler X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 19 Sep 2012 18:13:51 -0000 On Wed, Sep 19, 2012 at 07:12:50PM +0200, Roland Smith wrote: > On Tue, Sep 18, 2012 at 12:02:20AM +0200, Dimitry Andric wrote: > > On 2012-09-17 21:43, Roland Smith wrote: > > > On Wed, Sep 12, 2012 at 01:04:20AM -0500, Mark Linimon wrote: > > ... > > >> For most of the failures, we are already aware of them, as a result of > > >> our periodic runs. So, just filing a PR to say "broken on clang" doesn't > > >> really help us all that much. > > > > > > Those are build failures. What about crashes? E.g. I've recently had > > > crashes with x11-wm/i3 and x11/rxvt-unicode. Both problems disappeared after > > > recompiling them with gcc46. > > > > We can't figure them all out without *your* help. :-) Please attempt to > > run the program in a debugger, gather core dumps, etc. Or at least, try > > to make it into a reproducible case, so somebody else can attempt to > > diagnose it. And please specify the exact version of clang you used. > > I was using the clang that is in base in 9.0-RELEASE-p3: > > FreeBSD clang version 3.0 (branches/release_30 142614) 20111021 > Target: x86_64-unknown-freebsd9.0 > Thread model: posix > > I was thinking of installing the most recent clang-devel since it seemed to > have a lot of improvements, but I was wondering what is the correct way of > makeing sure that it is used in preference to the one in base? I thought about > moving /usr/local/bin before /usr/bin in $PATH, but I'm not sure that is a > good idea. > > > Now, most of the time this is because programs contain bugs, or > > undefined behavior, which happens to go unnoticed with gcc, for example > > because it optimized by accident in such a way to mask the bug. In a > > few other cases, real clang bugs are found, and most of the time, those > > can be fixed quickly. > > > > That said, in these cases specifically, how do the applications crash? > > Right at startup, or after specific inputs or user actions? > > Rxvt-unicode seemed to crash reliably whenever I was scrolling through a > document with less(1). If I reached the end of the document, and pressed Page > Down (keysim Next), it would crash. It was quite weird. > That sounds like the bell was doing it. If you do CTRL-G (or something else that makes a beep) from the shell prompt in rxvt-unicode does it also crash? Regards, Gary