From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 129647 invoked by alias); 23 Oct 2015 16:48:48 -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 128827 invoked by uid 89); 23 Oct 2015 16:48:48 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-2.4 required=5.0 tests=AWL,BAYES_00,RCVD_IN_DNSWL_LOW,SPF_PASS autolearn=ham version=3.3.2 X-HELO: relay1.mentorg.com Received: from relay1.mentorg.com (HELO relay1.mentorg.com) (192.94.38.131) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Fri, 23 Oct 2015 16:48:47 +0000 Received: from svr-orw-fem-06.mgc.mentorg.com ([147.34.97.120]) by relay1.mentorg.com with esmtp id 1ZpfWG-0001Sy-3z from Luis_Gustavo@mentor.com ; Fri, 23 Oct 2015 09:48:44 -0700 Received: from [172.30.0.18] (147.34.91.1) by SVR-ORW-FEM-06.mgc.mentorg.com (147.34.97.120) with Microsoft SMTP Server id 14.3.224.2; Fri, 23 Oct 2015 09:48:43 -0700 Reply-To: Luis Machado Subject: Re: [PATCH] Do not pass NULL for the string in catch_errors References: <1441809933-9612-1-git-send-email-lgustavo@codesourcery.com> <55F182B1.4020404@redhat.com> <5627739A.2090401@codesourcery.com> <5628C37E.2030208@redhat.com> <5628C715.5010701@codesourcery.com> <5628CD72.1080001@redhat.com> <5628D847.4050109@codesourcery.com> <5628E7F3.40708@redhat.com> To: Pedro Alves , From: Luis Machado Message-ID: <562A64E7.9040806@codesourcery.com> Date: Sat, 24 Oct 2015 22:39:00 -0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.3.0 MIME-Version: 1.0 In-Reply-To: <5628E7F3.40708@redhat.com> Content-Type: text/plain; charset="windows-1252"; format=flowed Content-Transfer-Encoding: 7bit X-IsSubscribed: yes X-SW-Source: 2015-10/txt/msg00504.txt.bz2 On 10/22/2015 11:43 AM, Pedro Alves wrote: > On 10/22/2015 01:36 PM, Luis Machado wrote: >> On 10/22/2015 09:50 AM, Pedro Alves wrote: >>> On 10/22/2015 12:23 PM, Luis Machado wrote: > >> That would be fine by me. I was just experimenting with >> TRY/CATCH/END_CATCH after my unsuccessful replacement of catch_errors >> with catch_exceptions. See below. >>>> > >>>> With catch_exceptions, instead of catching the error and letting the >>>> inferior continue, it will just cause the inferior to terminate. >>> >>> I don't understand. Why do you say this will happen? >>> >> >> I replaced catch_errors with catch_exceptions in record-full.c. I saw a >> bunch of failures in gdb.reverse/sigall-reverse.exp, starting at this point: >> >> Breakpoint 142, handle_TERM (sig=15) at >> ../../../gdb-head-ro/gdb/testsuite/gdb.reverse/sigall-reverse.c:378^M >> 378 }^M >> (gdb) PASS: gdb.reverse/sigall-reverse.exp: send signal TERM >> continue^M >> Continuing.^M >> The next instruction is syscall exit_group. It will make the program >> exit. Do you want to stop the program?([y] or n) yes^M >> Process record: inferior program stopped.^M >> ^M >> [process 21188] #1 stopped.^M >> >> The above is a normal run. If i replace catch_errors with >> catch_exceptions, instead of stopping the inferior, it will terminate. >> Maybe there is a bug somewhere, or something is being mishandled. > > It just sounds to me that you didn't take into account > that the return values of catch_errors and catch_exceptions > differ. > > while one does: > > if (exception.reason < 0) > { > ... > return exception.reason; > } > > the other does: > > if (exception.reason != 0) > return 0; > > This matters because the result is returned by > record_full_message_wrapper_safe, and checked here: > > if (!record_full_message_wrapper_safe (regcache, > GDB_SIGNAL_0)) > { > status->kind = TARGET_WAITKIND_STOPPED; > status->value.sig = GDB_SIGNAL_0; > break; > } > Indeed this is the case. I think i'll keep catch_errors and only fix the NULL parameter then. Having to adjust return values from unrelated functions sounds error-prone and maybe not worth it if we're moving away from these types of constructs in the future.