From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 2128 invoked by alias); 5 Feb 2014 19:11:59 -0000 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 Received: (qmail 2114 invoked by uid 89); 5 Feb 2014 19:11:59 -0000 Authentication-Results: sourceware.org; auth=none X-Spam-SWARE-Status: No, score=-2.0 required=5.0 tests=AWL,BAYES_00,RP_MATCHES_RCVD,SPF_HELO_PASS,SPF_PASS autolearn=ham version=3.3.2 X-HELO: mx1.redhat.com Received: from mx1.redhat.com (HELO mx1.redhat.com) (209.132.183.28) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Wed, 05 Feb 2014 19:11:58 +0000 Received: from int-mx10.intmail.prod.int.phx2.redhat.com (int-mx10.intmail.prod.int.phx2.redhat.com [10.5.11.23]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id s15JBrPN019867 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Wed, 5 Feb 2014 14:11:53 -0500 Received: from [127.0.0.1] (ovpn01.gateway.prod.ext.ams2.redhat.com [10.39.146.11]) by int-mx10.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id s15JBpim032340; Wed, 5 Feb 2014 14:11:52 -0500 Message-ID: <52F28CF7.8040206@redhat.com> Date: Wed, 05 Feb 2014 19:11:00 -0000 From: Pedro Alves User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130625 Thunderbird/17.0.7 MIME-Version: 1.0 To: Doug Evans CC: =?ISO-8859-1?Q?Ludovic_Court=E8s?= , "gdb-patches@sourceware.org" , saugustine@google.com Subject: Re: Fun with LD_PRELOAD References: <8761ovp1hw.fsf@gnu.org> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-SW-Source: 2014-02/txt/msg00046.txt.bz2 (removed guile) As we're talking about it, On 02/05/2014 06:21 PM, Doug Evans wrote: > For example, a colleague at Google tripped over a bug that requires a > specific timing to replicate. I don't have all the details at hand, > but I think I'm hitting the same assert. > > infrun.c:1948: internal-error: resume: Assertion > `pc_in_thread_step_range (pc, tp)' failed. > > AIUI, It happens, for example, when the user does a "next", and a > signal arrives on another thread while the thread being next'd has > stepped into a subroutine (thus requiring gdb to step out to implement > the semantics of "next"). I now have a simple repro (at least for the > assert I'm seeing), and it was very straightforward to write. It > involves tracking the PTRACE_SINGLESTEP being issued to one thread > (that implement "next") and at the right time send a signal to another > thread. perhaps you could check whether the patch at https://sourceware.org/ml/gdb-patches/2014-01/msg00910.html also fixes your reproducer? -- Pedro Alves