From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 23757 invoked by alias); 20 Nov 2001 00:42:47 -0000 Mailing-List: contact gdb-patches-help@sourceware.cygnus.com; run by ezmlm Precedence: bulk List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sources.redhat.com Received: (qmail 23668 invoked from network); 20 Nov 2001 00:42:44 -0000 Received: from unknown (HELO cygnus.com) (205.180.230.5) by sourceware.cygnus.com with SMTP; 20 Nov 2001 00:42:44 -0000 Received: from cse.cygnus.com (cse.cygnus.com [205.180.230.236]) by runyon.cygnus.com (8.8.7-cygnus/8.8.7) with ESMTP id QAA25077; Mon, 19 Nov 2001 16:42:40 -0800 (PST) Received: (from kev@localhost) by cse.cygnus.com (8.9.3/8.9.3) id RAA17106; Mon, 19 Nov 2001 17:42:30 -0700 Date: Wed, 07 Nov 2001 19:05:00 -0000 From: Kevin Buettner Message-Id: <1011120004229.ZM17105@ocotillo.lan> In-Reply-To: "H . J . Lu" "Re: [PATCH RFA] lin-lwp.c: Block SIGCHLD events when attaching" (Nov 19, 11:38am) References: <1011119193045.ZM16376@ocotillo.lan> <20011119113832.A8778@lucon.org> X-Mailer: Z-Mail (4.0.1 13Jan97 Caldera) To: "H . J . Lu" Subject: Re: [PATCH RFA] lin-lwp.c: Block SIGCHLD events when attaching Cc: gdb-patches@sources.redhat.com MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-SW-Source: 2001-11/txt/msg00135.txt.bz2 On Nov 19, 11:38am, H . J . Lu wrote: > On Mon, Nov 19, 2001 at 12:30:45PM -0700, Kevin Buettner wrote: > > When doing a lin_lwp_attach_lwp(), it is sometimes possible to receive > > a SIGCHLD signal thus causing the waitpid() call to fail with EINTR. > > This in turn causes the second assert() in lin_lwp_attach_lwp() to > > fail. > > > > Reproducing this problem can be somewhat difficult. I've only been > > able to reproduce it on a dual processor Linux/x86 machine. I did > > manage to reproduce it using the linux-dp program as follows: > > > > Have you looked at > > http://sources.redhat.com/ml/gdb/2001-09/msg00139.html > > Specifically, > > # gcc -g ex11.c -lpthread -lrt -D_GNU_SOURCE -static > # a.out > # gdb a.out > ... > (gdb) att 14226 > Attaching to program: /home/hjl/bugs/gdb/thread/a.out, process 14226 > ... > lin-lwp.c:620: gdb-internal-error: stop_wait_callback: Assertion `pid == GET_LWP (lp->ptid)' failed. > An internal GDB error was detected. This may make further > > ex11.c is from glibc and 14226 is the first thread. Your patch may fix > it also. I think this might be a different problem. I haven't been able to reproduce the exact problem that you mentioned above, either with or without my patch. I do occassionally see "Cannot find new threads: generic error". I'm going to try to figure this one out... Kevin