From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 746 invoked by alias); 10 Dec 2005 19:58:44 -0000 Received: (qmail 739 invoked by uid 22791); 10 Dec 2005 19:58:43 -0000 X-Spam-Check-By: sourceware.org Received: from 203.197.88.2.ILL-PUNE.static.vsnl.net.in (HELO marvin.codito.net) (203.197.88.2) by sourceware.org (qpsmtpd/0.31) with ESMTP; Sat, 10 Dec 2005 19:58:41 +0000 Received: from [192.168.1.5] (DSL-TN-235.24.144.59.touchtelindia.net [59.144.24.235] (may be forged)) (authenticated bits=0) by marvin.codito.net (8.13.5/8.13.5/Debian-3) with ESMTP id jBAJrPqF023028; Sun, 11 Dec 2005 01:27:04 +0530 Subject: Re: Watchpoint segfaults From: Ramana Radhakrishnan Reply-To: ramana@codito.com To: Daniel Jacobowitz Cc: gdb@sourceware.org In-Reply-To: <20051210155740.GA9227@nevyn.them.org> References: <20051209195811.GA19885@nevyn.them.org> <20051210155740.GA9227@nevyn.them.org> Content-Type: text/plain Date: Sat, 10 Dec 2005 19:58:00 -0000 Message-Id: <1134244480.8403.20.camel@localhost.localdomain> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit X-Virus-Status: Clean X-IsSubscribed: yes Mailing-List: contact gdb-help@sourceware.org; run by ezmlm Precedence: bulk List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-owner@sourceware.org X-SW-Source: 2005-12/txt/msg00121.txt.bz2 Hi Daniel, On Sat, 2005-12-10 at 10:57 -0500, Daniel Jacobowitz wrote: > On Sat, Dec 10, 2005 at 10:31:02AM +0200, Eli Zaretskii wrote: > > > Date: Fri, 9 Dec 2005 14:58:11 -0500 > > > From: Daniel Jacobowitz > > > > > > I think we want to temporarily disable breakpoints whose expression can't be > > > parsed > > > > I agree. But perhaps instead of just disabling it we should display > > some warning the first time we find that we are unable to parse its > > expression. > > That sounds like a good idea. We should also try to re-parse it at any > available opportunity, e.g. when the symbol table changes. This'll > take a little work to get right. I am not too clear about this. Do you mean observer_notify_executable_changed but that does not get called in case of add-symbol-file where the symtab could change again and you have potential cases there ? There used to be a file_changed_hook where we might be able to do this but thats been deprecated here . http://sources.redhat.com/ml/gdb-patches/2004-04/msg00271.html > > > > and print it as a string rather than using the expression printer. > > > > Print it where? in the table displayed by "info breakpoints" or > > equivalent commands? Or do you have some other situation in mind? > > Sorry, yes, I was referring to the "info breakpoints" segfault. > Basically someone's going to have to go through and audit the uses of > ->exp. This is a rather simplistic fix which does not yet disable the watchpoint but prevents the segfault . I did on the 6.4 branch since that is what I have handy . Also the other occurences of print_expression with -->exp that I could find were in mention in which case you do have a symbol table already created and if the symbol were not there an automatic error would be raised much in advance. Is there any other usecase you had in mind ? cheers Ramana Index: breakpoint.c =================================================================== RCS file: /cvs/src/src/gdb/breakpoint.c,v retrieving revision 1.217 diff -a -u -r1.217 breakpoint.c --- breakpoint.c 29 May 2005 03:13:17 -0000 1.217 +++ breakpoint.c 10 Dec 2005 19:38:54 -0000 @@ -3387,7 +3387,10 @@ if (addressprint) ui_out_field_skip (uiout, "addr"); annotate_field (5); - print_expression (b->exp, stb->stream); + if (b->exp) + print_expression (b->exp, stb->stream); + else + ui_out_field_string (uiout,"what", b->exp_string); ui_out_field_stream (uiout, "what", stb); break;