From owner-freebsd-arch@FreeBSD.ORG Tue Apr 8 21:43:18 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 0464E722 for ; Tue, 8 Apr 2014 21:43:18 +0000 (UTC) Received: from mail-pd0-f178.google.com (mail-pd0-f178.google.com [209.85.192.178]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id CA86618FA for ; Tue, 8 Apr 2014 21:43:17 +0000 (UTC) Received: by mail-pd0-f178.google.com with SMTP id x10so1541590pdj.23 for ; Tue, 08 Apr 2014 14:43:11 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:sender:content-type:mime-version:subject:from :in-reply-to:date:cc:content-transfer-encoding:message-id:references :to; bh=UrvBY7QDP21jHZ4q9QOb7XbHiLDdK4iw1PnTXN36AYo=; b=drxxNbJdjjela2QOMSWcxhJcZKanY7e9eO9e/NnAR14w9BKiKfAQVJEpXgdzbmCgfr BVUGLVhvElcabsjG73KguKSgcr8hYduWCs1K/BUvIs6nrdGPwjFRKnnPVoKUX0mOXmCW C5IiGZzQvoLz57jFeoRX01LxclMoy4sGSvsak+uml2om2So277jYpWVB3zCmNEsDhMC/ oqj8HmM3YDRy8QbUVOSiuHm1I90JPN+TDySUudqtvBttsX/Bx7+60OpfuWdJNRV81vjI jiOod3cpq9XY9T98HvJ58IndU4tCdmbYc4TqeDUUrdkUZZwbF1Y4V/UK1/7bfm15JC+h Fj0g== X-Gm-Message-State: ALoCoQlUaTYq2SO4LQWxOpZXfdx4rGHaDNV58bBezC+0jDtDF3QwAT9a/HNPFLpWqhNFRsPjhdTX X-Received: by 10.68.240.5 with SMTP id vw5mr7225049pbc.113.1396993391018; Tue, 08 Apr 2014 14:43:11 -0700 (PDT) Received: from [10.64.24.116] (dc1-prod.netflix.com. [69.53.236.251]) by mx.google.com with ESMTPSA id sm5sm15554245pab.19.2014.04.08.14.43.09 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Tue, 08 Apr 2014 14:43:10 -0700 (PDT) Sender: Warner Losh Content-Type: text/plain; charset=windows-1252 Mime-Version: 1.0 (Mac OS X Mail 7.2 \(1874\)) Subject: Re: Time for turning off gdb by default? Or worse... From: Warner Losh In-Reply-To: <20140408212435.GA75404@troutmask.apl.washington.edu> Date: Tue, 8 Apr 2014 15:43:08 -0600 Content-Transfer-Encoding: quoted-printable Message-Id: <57ECB078-3D7A-4BE8-AA29-1ED7BB347DBD@bsdimp.com> References: <20140408212435.GA75404@troutmask.apl.washington.edu> To: Steve Kargl X-Mailer: Apple Mail (2.1874) Cc: 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 21:43:18 -0000 On Apr 8, 2014, at 3:24 PM, Steve Kargl = wrote: > 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? Doesn=92t matter. > 2) What effect does this have on kgdb? Note, /sys/conf/NOTES contains Unfortunately, kgdb isn=92t available as a port, so that does matter. It = is one thing arguing against this change. > #makeoptions DEBUG=3D-g #Build kernel with gdb(1) debug = symbols >=20 > Should this be updates to DEBUG=3D-gdwarf-2? Nope. It should stay exactly as it is. We convert -g to -gdwarf-2 for = those compilers that need it. > PS: You'll need to sweep src/ for references to gdb(1). No. It is just not built by default, not being kicked out of the tree. Warner