From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 5109 invoked by alias); 11 Jun 2008 17:36:52 -0000 Received: (qmail 5101 invoked by uid 22791); 11 Jun 2008 17:36:51 -0000 X-Spam-Check-By: sourceware.org Received: from NaN.false.org (HELO nan.false.org) (208.75.86.248) by sourceware.org (qpsmtpd/0.31) with ESMTP; Wed, 11 Jun 2008 17:36:30 +0000 Received: from nan.false.org (localhost [127.0.0.1]) by nan.false.org (Postfix) with ESMTP id D373A98366; Wed, 11 Jun 2008 17:36:28 +0000 (GMT) Received: from caradoc.them.org (22.svnf5.xdsl.nauticom.net [209.195.183.55]) by nan.false.org (Postfix) with ESMTP id 9C2859805C; Wed, 11 Jun 2008 17:36:28 +0000 (GMT) Received: from drow by caradoc.them.org with local (Exim 4.69) (envelope-from ) id 1K6UFG-0006b7-Vf; Wed, 11 Jun 2008 13:36:26 -0400 Date: Wed, 11 Jun 2008 17:36:00 -0000 From: Daniel Jacobowitz To: Vladimir Prus Cc: gdb@sources.redhat.com, Pedro Alves , Hamish Rodda Subject: Re: SIGCHLD ignored Message-ID: <20080611173626.GA25045@caradoc.them.org> Mail-Followup-To: Vladimir Prus , gdb@sources.redhat.com, Pedro Alves , Hamish Rodda References: <200806112121.06783.ghost@cs.msu.su> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200806112121.06783.ghost@cs.msu.su> User-Agent: Mutt/1.5.17 (2008-05-11) X-IsSubscribed: yes 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 X-SW-Source: 2008-06/txt/msg00100.txt.bz2 On Wed, Jun 11, 2008 at 09:21:05PM +0400, Vladimir Prus wrote: > > A fellow KDevelop hacker has reported that when running kdevelop itself > under CVS HEAD of gdb, kdevelop hangs. What happens if that kdevelop spawns > subprocess, and then does not notice it has exited, because it never > receives SIGCHLD. I attach a much reduced project that requires only Qt4, > and probably an even more reduced project is possible. > > If I apply the attached patch to GDB, things work fine -- but I suspect > this 'fix' will break something else. > > Pedro, I think this SIGCHLD magic is your doing -- do you have any ideas > how to fix it? linux_nat_create_inferior is already unblocking signals before creating. Does normal_mask contain SIGCHLD? The approach taken (search for "signal" in fork-child.c, first comment) may not be compatible with async... -- Daniel Jacobowitz CodeSourcery