From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 13943 invoked by alias); 24 Jun 2005 18:52:53 -0000 Mailing-List: contact gdb-help@sources.redhat.com; run by ezmlm Precedence: bulk List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-owner@sources.redhat.com Received: (qmail 13927 invoked by uid 22791); 24 Jun 2005 18:52:51 -0000 Received: from mail-out4.apple.com (HELO mail-out4.apple.com) (17.254.13.23) by sourceware.org (qpsmtpd/0.30-dev) with ESMTP; Fri, 24 Jun 2005 18:52:51 +0000 Received: from mailgate1.apple.com (a17-128-100-225.apple.com [17.128.100.225]) by mail-out4.apple.com (8.12.11/8.12.11) with ESMTP id j5OIqmL1025140 for ; Fri, 24 Jun 2005 11:52:49 -0700 (PDT) Received: from relay3.apple.com (relay3.apple.com) by mailgate1.apple.com (Content Technologies SMTPRS 4.3.17) with ESMTP id for ; Fri, 24 Jun 2005 11:52:48 -0700 Received: from [17.201.22.21] (moleja.apple.com [17.201.22.21]) by relay3.apple.com (8.12.11/8.12.11) with ESMTP id j5OIqmYi024194 for ; Fri, 24 Jun 2005 11:52:48 -0700 (PDT) Mime-Version: 1.0 (Apple Message framework v728) In-Reply-To: <20050624151129.GH66895@keyslapper.net> References: <20050624151129.GH66895@keyslapper.net> Content-Type: text/plain; charset=US-ASCII; delsp=yes; format=flowed Message-Id: <1736E276-B5AE-489B-8538-2BEDFB97C4DB@apple.com> Content-Transfer-Encoding: 7bit From: Jason Molenda Subject: Re: aborted thread backtrace stops at sighandler call Date: Fri, 24 Jun 2005 18:52:00 -0000 To: GDB question X-SW-Source: 2005-06/txt/msg00240.txt.bz2 On Jun 24, 2005, at 8:11 AM, Louis LeBlanc wrote: > Anyone have any idea how to get this? > > This is the backtrace for the aborted thread: > (gdb) bt > #0 0xfea1f82c in __tbl_2_huge_digits () from /usr/lib/libc.so.1 > #1 0xfe9d0a24 in sysconf () from /usr/lib/libc.so.1 > #2 0xfe9b6ce0 in ascftime () from /usr/lib/libc.so.1 > #3 0x0003c72c in XPCSigCheck (Sig=11, Info=0xfe776ad0, > Context=0xfe776818) at xpcsig.c:347 > #4 0xff365b14 in ?? () > #5 0xff365b18 in ?? () > Previous frame identical to this frame (corrupt stack?) > > But pstack shows this: > ----------------- lwp# 3 / thread# 3 -------------------- > fea1f82c _lwp_kill (6, 0, fe7765b8, fe776630, 0, 1) + 8 > fe9b6cd8 abort (df708, 0, 0, 0, 0, 0) + 100 > 0003c724 XPCSigCheck (b, fe776ad0, fe776818, 0, 0, 0) + 2c0 > ff365b0c __sighndlr (b, fe776ad0, fe776818, 3c464, 0, 0) + c > ff35f804 call_user_handler (b, fe776ad0, fe776818, 0, 0, 0) + 234 > ff35f9b4 sigacthandler (b, fe776ad0, fe776818, 7efefeff, 81010100, > 0) + 64 > --- called from signal handler with signal 11 (SIGSEGV) --- I don't have anything better than Daniel to suggest, but the problem here is specifically that backtracing through a signal handler is a special case -- it's the most fragile part of any backtracer in gdb -- and that's where your back trace is failing. J