From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 27426 invoked by alias); 3 Nov 2011 17:22:54 -0000 Received: (qmail 27415 invoked by uid 22791); 3 Nov 2011 17:22:53 -0000 X-SWARE-Spam-Status: No, hits=-7.2 required=5.0 tests=AWL,BAYES_00,RCVD_IN_DNSWL_HI,RP_MATCHES_RCVD,SPF_HELO_PASS 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; Thu, 03 Nov 2011 17:22:36 +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 pA3HMZiB008258 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Thu, 3 Nov 2011 13:22:35 -0400 Received: from host1.jankratochvil.net (ovpn-116-23.ams2.redhat.com [10.36.116.23]) by int-mx02.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id pA3HMX8h007452 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Thu, 3 Nov 2011 13:22:34 -0400 Received: from host1.jankratochvil.net (localhost [127.0.0.1]) by host1.jankratochvil.net (8.14.4/8.14.4) with ESMTP id pA3HMWeN023488; Thu, 3 Nov 2011 18:22:32 +0100 Received: (from jkratoch@localhost) by host1.jankratochvil.net (8.14.4/8.14.4/Submit) id pA3HMW9M023487; Thu, 3 Nov 2011 18:22:32 +0100 Date: Thu, 03 Nov 2011 17:22:00 -0000 From: Jan Kratochvil To: Michael Eager Cc: Tom Tromey , "gdb-patches@sourceware.org" Subject: Re: SEGV in dwarf2read.c -- gdb-7.2 Message-ID: <20111103172232.GA23268@host1.jankratochvil.net> References: <4EB2BD58.3080003@eagerm.com> <20111103162026.GA12269@host1.jankratochvil.net> <20111103165521.GA16221@host1.jankratochvil.net> <4EB2CBA0.7030307@eagerm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4EB2CBA0.7030307@eagerm.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-IsSubscribed: yes 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: 2011-11/txt/msg00087.txt.bz2 On Thu, 03 Nov 2011 18:13:04 +0100, Michael Eager wrote: > With the addition of the call to age_cached_comp_units() in > dwarf2_fetch_die_location_block() and dw2_do_instantiate_symtab(), > I think that the cache is aged very aggressively. > With dwarf2_max_cache_age == 5, it looks to me that it is likely that CU > data will not be in the cache when needed. There was for example this fix: http://sourceware.org/ml/gdb-patches/2011-07/msg00495.html which is not yet even in 7.3.1 as I see now, it is only in FSF GDB HEAD. wrt CUs aging therefore only FSF GDB HEAD matters, older releases are known to be buggy - at least due to this bug. With FSF GDB HEAD I am not aware of any problems because any call to age_cached_comp_units is done when CUs are no longer needed anywhere. I do not discuss here about efficiency of the FSF GDB HEAD solution but I am not aware of how it could crash any way. Thanks, Jan