From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 12163 invoked by alias); 24 Jul 2009 22:47:17 -0000 Received: (qmail 12146 invoked by uid 22791); 24 Jul 2009 22:47:15 -0000 X-SWARE-Spam-Status: No, hits=-2.3 required=5.0 tests=AWL,BAYES_00,SPF_HELO_PASS,SPF_PASS X-Spam-Check-By: sourceware.org Received: from mx2.redhat.com (HELO mx2.redhat.com) (66.187.237.31) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Fri, 24 Jul 2009 22:47:09 +0000 Received: from int-mx2.corp.redhat.com (int-mx2.corp.redhat.com [172.16.27.26]) by mx2.redhat.com (8.13.8/8.13.8) with ESMTP id n6OMj5S6011623; Fri, 24 Jul 2009 18:45:05 -0400 Received: from ns3.rdu.redhat.com (ns3.rdu.redhat.com [10.11.255.199]) by int-mx2.corp.redhat.com (8.13.1/8.13.1) with ESMTP id n6OMj3bJ012645; Fri, 24 Jul 2009 18:45:03 -0400 Received: from opsy.redhat.com (ovpn01.gateway.prod.ext.phx2.redhat.com [10.5.9.1]) by ns3.rdu.redhat.com (8.13.8/8.13.8) with ESMTP id n6OMj2DJ002200; Fri, 24 Jul 2009 18:45:02 -0400 Received: by opsy.redhat.com (Postfix, from userid 500) id 5DCBC5081C2; Fri, 24 Jul 2009 16:45:02 -0600 (MDT) To: Pedro Alves Cc: gdb-patches@sourceware.org, "Ulrich Weigand" , Jan Kratochvil Subject: Multi-exec patches (Was: [rfc] Infrastructure to disable breakpoints during inferior startup) References: <200907231631.n6NGV2xR018887@d12av02.megacenter.de.ibm.com> <200907231751.01413.pedro@codesourcery.com> From: Tom Tromey Reply-To: Tom Tromey Date: Fri, 24 Jul 2009 23:32:00 -0000 In-Reply-To: (Tom Tromey's message of "Fri\, 24 Jul 2009 16\:05\:27 -0600") Message-ID: User-Agent: Gnus/5.11 (Gnus v5.11) Emacs/22.3 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii 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 X-SW-Source: 2009-07/txt/msg00611.txt.bz2 >>>>> "Tom" == Tom Tromey writes: Tom> I still haven't actually tried it, but I hope to do so soon. I tried it a little. I can't remember ... should this all work ok on x86 Linux? I thought yes, hence this report, but if not, feel free to just let me know and ignore all this. Most of what I've written here seems familiar. I assume I read it all in earlier notes of yours :-) The first thing I noticed is that the new features are off by default. I had to: set schedule-multiple on set detach-on-fork off to get it to work. Having it disabled by default is ok as long as it is a "technology preview", but if we think it is very solid then I think we should enable it by default. Having to set 2 options is obscure. I suppose I didn't really need to set both, except my first attempt was to run "make", which tripped over the vfork problem. I put a gcc I built into my $PATH. Then I did: $ cd gdbserver $ ../gdb make Then I tried various things. "run clean" worked ok! That was cool! Then I exited gdb and restarted it and tried a plain "run". This gave me: (gdb) set schedule-multiple on (gdb) set detach-on-fork off (gdb) run Starting program: /usr/bin/make (no debugging symbols found) (no debugging symbols found) (no debugging symbols found) [New process 3931] process 3931 is executing new program: /bin/true (no debugging symbols found) (no debugging symbols found) (no debugging symbols found) Program exited normally. ... which is a little odd, since no build was done. And, what's with process 3931 executing /bin/true? Am I not debugging the 'make' process? A minor nit: I think "is executing a new program" would read better. Then I did "run clean": (gdb) run clean Starting program: /bin/true clean (no debugging symbols found) (no debugging symbols found) gcc -c -Wall -g3 -I. -I../../../archer/gdb/gdbserver -I../../../archer/gdb/gdbserver/../common -I../../../archer/gdb/gdbserver/../regformats -I../../../archer/gdb/gdbserver/../../include ../../../archer/gdb/gdbserver/regcache.c Here, for some reason, the compile started. And, gdb forgot that I was looking at "make" and ran /bin/true. At this point, gdb hangs and cannot be interrupted. I kill -9'd it. If I do the above but remember "file /usr/bin/make", gdb starts make again ok and the compile starts. But, gdb hangs again as above. This hang occurs often enough that I couldn't get to other tests, like trying to set a breakpoint that would only trigger in cc1. Those "(no debugging symbols found)" messages made me want Doug's patch more ;) Note that it is entirely possible that the patch applied strangely and I introduced some bug that way. Or, maybe there is some other pilot error. Tom