From owner-freebsd-arch@FreeBSD.ORG Tue Apr 8 22:17:11 2014 Return-Path: Delivered-To: freebsd-arch@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id E946740C for ; Tue, 8 Apr 2014 22:17:11 +0000 (UTC) Received: from mho-01-ewr.mailhop.org (mho-03-ewr.mailhop.org [204.13.248.66]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id BA22F1BF3 for ; Tue, 8 Apr 2014 22:17:11 +0000 (UTC) Received: from c-24-8-230-52.hsd1.co.comcast.net ([24.8.230.52] helo=damnhippie.dyndns.org) by mho-01-ewr.mailhop.org with esmtpsa (TLSv1:AES256-SHA:256) (Exim 4.72) (envelope-from ) id 1WXeKM-0008aV-63; Tue, 08 Apr 2014 22:17:10 +0000 Received: from [172.22.42.240] (revolution.hippie.lan [172.22.42.240]) by damnhippie.dyndns.org (8.14.3/8.14.3) with ESMTP id s38MH7qS093170; Tue, 8 Apr 2014 16:17:07 -0600 (MDT) (envelope-from ian@FreeBSD.org) X-Mail-Handler: Dyn Standard SMTP by Dyn X-Originating-IP: 24.8.230.52 X-Report-Abuse-To: abuse@dyndns.com (see http://www.dyndns.com/services/sendlabs/outbound_abuse.html for abuse reporting information) X-MHO-User: U2FsdGVkX1+JfnYozdJmDKkMdVZndhTy Subject: Re: Time for turning off gdb by default? Or worse... From: Ian Lepore To: Warner Losh In-Reply-To: <57ECB078-3D7A-4BE8-AA29-1ED7BB347DBD@bsdimp.com> References: <20140408212435.GA75404@troutmask.apl.washington.edu> <57ECB078-3D7A-4BE8-AA29-1ED7BB347DBD@bsdimp.com> Content-Type: text/plain; charset="iso-8859-7" Date: Tue, 08 Apr 2014 16:17:07 -0600 Message-ID: <1396995427.81853.449.camel@revolution.hippie.lan> Mime-Version: 1.0 X-Mailer: Evolution 2.32.1 FreeBSD GNOME Team Port Content-Transfer-Encoding: quoted-printable X-MIME-Autoconverted: from 8bit to quoted-printable by damnhippie.dyndns.org id s38MH7qS093170 Cc: Steve Kargl , freebsd-arch X-BeenThere: freebsd-arch@freebsd.org X-Mailman-Version: 2.1.17 Precedence: list List-Id: Discussion related to FreeBSD architecture List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 08 Apr 2014 22:17:12 -0000 On Tue, 2014-04-08 at 15:43 -0600, Warner Losh wrote: > On Apr 8, 2014, at 3:24 PM, Steve Kargl wrote: >=20 > > On Tue, Apr 08, 2014 at 02:34:35PM -0600, Warner Losh wrote: > >=20 > > (courtesy line wrap to something well below 80 characters) > >=20 > >> The gdb in the tree seems to be of very limited usefulness > >> these days. It doesn?t seem to work on clang-enabled > >> architectures w/o building -gdwarf-2, it doesn?t seem to work > >> with threaded applications, and on some architectures it > >> doesn?t seem to work at all (mips comes to mind, but it may > >> have been the two binaries I tried). > >>=20 > >=20 > > (patch removed) > >=20 > >> to the tree, which will turn gdb off by default. It may make > >> more sense to just remove it entirely, but I?m not sure I want > >> to go there just yet in case there are things that I?m missing. > >> I believe that the port will be adequate for all architectures > >> we support, but haven?t tested this directly yet. I do know > >> that on amd64, the port just worked, where the in-tree gdb > >> was an epic fail. > >=20 > > I suppose the obvious questions are: > >=20 > > 1) Is lldb ready for prime time? >=20 > Doesn=A2t matter. >=20 > > 2) What effect does this have on kgdb? Note, /sys/conf/NOTES contain= s >=20 > Unfortunately, kgdb isn=A2t available as a port, so that does matter. I= t is one thing arguing against this change. >=20 > > #makeoptions DEBUG=3D-g #Build kernel with gdb(1) debug symbols > >=20 > > Should this be updates to DEBUG=3D-gdwarf-2? >=20 > Nope. It should stay exactly as it is. We convert -g to -gdwarf-2 for t= hose compilers that need it. Only when building the kernel. For userland we've got nothing. gdb aside, even addr2line doesn't work on userland binaries anymore. It used to be hard to do debugging for arm. Now it's impossible. -- Ian