From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 7322 invoked by alias); 5 Jun 2012 19:24:34 -0000 Received: (qmail 7313 invoked by uid 22791); 5 Jun 2012 19:24:34 -0000 X-SWARE-Spam-Status: No, hits=-7.5 required=5.0 tests=AWL,BAYES_00,KHOP_RCVD_UNTRUST,KHOP_THREADED,RCVD_IN_DNSWL_HI,RCVD_IN_HOSTKARMA_W,SPF_HELO_PASS,T_RP_MATCHES_RCVD X-Spam-Check-By: sourceware.org Received: from mx1.redhat.com (HELO mx1.redhat.com) (209.132.183.28) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Tue, 05 Jun 2012 19:24:17 +0000 Received: from int-mx02.intmail.prod.int.phx2.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id q55JOHC9013930 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Tue, 5 Jun 2012 15:24:17 -0400 Received: from [127.0.0.1] (ovpn01.gateway.prod.ext.ams2.redhat.com [10.39.146.11]) by int-mx02.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id q55JOFZI026504; Tue, 5 Jun 2012 15:24:16 -0400 Message-ID: <4FCE5CDF.7070407@redhat.com> Date: Tue, 05 Jun 2012 19:24:00 -0000 From: Pedro Alves User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:12.0) Gecko/20120430 Thunderbird/12.0.1 MIME-Version: 1.0 To: Jan Kratochvil CC: gdb-patches@sourceware.org Subject: Re: [downstream patch FYI] workaround stale frame_info * (PR 13866) References: <20120404191416.GA29603@host2.jankratochvil.net> In-Reply-To: <20120404191416.GA29603@host2.jankratochvil.net> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit 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: 2012-06/txt/msg00152.txt.bz2 On 04/04/2012 08:14 PM, Jan Kratochvil wrote: > > Reproducer with: > ./gdb -nx ~/t/thread -ex 'b 24' -ex r -ex 'until 25' > Breakpoint 1, main () at /home/jkratoch/t/thread.c:24 > 24 v++; > Segmentation fault (core dumped) > > #include > #include > #include > > static int v; > > static void *start (void *arg) > { > v++; > v++; > v++; > v++; > sleep (100); > return arg; > } > > int main (void) > { > pthread_t thread1; > int i; > > i = pthread_create (&thread1, NULL, start, NULL); > assert (i == 0); > v++; > v++; > v++; > v++; > i = pthread_join (thread1, NULL); > assert (i == 0); > > return 0; > } This fixes the crash. 2012-06-05 Pedro Alves PR backtrace/13866 * breakpoint.c (until_break_command): Only fetch the selected frame after decode_line_1. --- gdb/breakpoint.c | 13 +++++++++---- 1 files changed, 9 insertions(+), 4 deletions(-) diff --git a/gdb/breakpoint.c b/gdb/breakpoint.c index 5cc1f64..9757d0d 100644 --- a/gdb/breakpoint.c +++ b/gdb/breakpoint.c @@ -10815,10 +10815,10 @@ until_break_command (char *arg, int from_tty, int anywhere) { struct symtabs_and_lines sals; struct symtab_and_line sal; - struct frame_info *frame = get_selected_frame (NULL); - struct gdbarch *frame_gdbarch = get_frame_arch (frame); - struct frame_id stack_frame_id = get_stack_frame_id (frame); - struct frame_id caller_frame_id = frame_unwind_caller_id (frame); + struct frame_info *frame; + struct gdbarch *frame_gdbarch; + struct frame_id stack_frame_id; + struct frame_id caller_frame_id; struct breakpoint *breakpoint; struct breakpoint *breakpoint2 = NULL; struct cleanup *old_chain; @@ -10854,6 +10854,11 @@ until_break_command (char *arg, int from_tty, int anywhere) old_chain = make_cleanup (null_cleanup, NULL); + frame = get_selected_frame (NULL); + frame_gdbarch = get_frame_arch (frame); + stack_frame_id = get_stack_frame_id (frame); + caller_frame_id = frame_unwind_caller_id (frame); + /* Installing a breakpoint invalidates the frame chain (as it may need to switch threads), so do any frame handling first. */