From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 52298 invoked by alias); 2 Nov 2015 21:09:53 -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 52284 invoked by uid 89); 2 Nov 2015 21:09:52 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-1.9 required=5.0 tests=AWL,BAYES_00,SPF_HELO_PASS,T_RP_MATCHES_RCVD 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 (AES256-GCM-SHA384 encrypted) ESMTPS; Mon, 02 Nov 2015 21:09:51 +0000 Received: from int-mx13.intmail.prod.int.phx2.redhat.com (int-mx13.intmail.prod.int.phx2.redhat.com [10.5.11.26]) by mx1.redhat.com (Postfix) with ESMTPS id B3CAD8F268; Mon, 2 Nov 2015 21:09:50 +0000 (UTC) Received: from [127.0.0.1] (ovpn01.gateway.prod.ext.ams2.redhat.com [10.39.146.11]) by int-mx13.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id tA2L9nQq023362; Mon, 2 Nov 2015 16:09:49 -0500 Message-ID: <5637D11C.3030704@redhat.com> Date: Mon, 02 Nov 2015 21:09:00 -0000 From: Pedro Alves User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.7.0 MIME-Version: 1.0 To: Simon Marchi , gdb-patches@sourceware.org Subject: Re: [PATCH 08/11] [C++/mingw] Simplify first chance exception handling References: <1446492970-21432-1-git-send-email-palves@redhat.com> <1446492970-21432-9-git-send-email-palves@redhat.com> <5637CF3B.9060806@ericsson.com> In-Reply-To: <5637CF3B.9060806@ericsson.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit X-SW-Source: 2015-11/txt/msg00055.txt.bz2 On 11/02/2015 09:01 PM, Simon Marchi wrote: > Does this change fix something initially related to C++? Whoops, forgot to mention that in the commit log. Now updated. >From b2759c57612aa28d19b140a7edf5bac57982564b Mon Sep 17 00:00:00 2001 From: Pedro Alves Date: Fri, 30 Oct 2015 20:49:06 +0000 Subject: [PATCH] [C++/mingw] Simplify first chance exception handling Building in C++ errors out with: ../../src/gdb/windows-nat.c: In function 'int get_windows_debug_event(target_ops*, int, target_waitstatus*)': ../../src/gdb/windows-nat.c:1503:13: warning: invalid conversion from 'int' to 'gdb_signal' [-fpermissive] last_sig = 1; ^ ../../src/gdb/windows-nat.c:1533:43: warning: invalid conversion from 'int' to 'gdb_signal' [-fpermissive] windows_resume (ops, minus_one_ptid, 0, 1); ^ ../../src/gdb/windows-nat.c:1228:1: warning: initializing argument 4 of 'void windows_resume(target_ops*, ptid_t, int, gdb_signal)' [-fpermissive] windows_resume (struct target_ops *ops, ^ Looking at the code, I can't figure out why we treat first chance exceptions any different here. AFAICS, we set last_sig to 1, and then call windows_resume passing signal==1, so the DBG_EXCEPTION_NOT_HANDLED code path in win32_resume is taken: ~~~ if (sig != GDB_SIGNAL_0) { if (current_event.dwDebugEventCode != EXCEPTION_DEBUG_EVENT) { OUTMSG (("Cannot continue with signal %d here.\n", sig)); } else if (sig == last_sig) continue_status = DBG_EXCEPTION_NOT_HANDLED; else OUTMSG (("Can only continue with recieved signal %d.\n", last_sig)); } ~~~ Fix this by removing this special casing. gdbserver also goes straight to continuing with DBG_EXCEPTION_NOT_HANDLED, AFAICS. gdb/ChangeLog: 2015-11-01 Pedro Alves * windows-nat.c (handle_exception): Return 0 for first chance exceptions. (get_windows_debug_event): Adjust. --- gdb/windows-nat.c | 24 ++++++------------------ 1 file changed, 6 insertions(+), 18 deletions(-) diff --git a/gdb/windows-nat.c b/gdb/windows-nat.c index cce10f8..a7132d6 100644 --- a/gdb/windows-nat.c +++ b/gdb/windows-nat.c @@ -1124,7 +1124,7 @@ handle_exception (struct target_waitstatus *ourstatus) default: /* Treat unhandled first chance exceptions specially. */ if (current_event.u.Exception.dwFirstChance) - return -1; + return 0; printf_unfiltered ("gdb: unknown target exception 0x%08x at %s\n", (unsigned) current_event.u.Exception.ExceptionRecord.ExceptionCode, host_address_to_string ( @@ -1491,19 +1491,10 @@ get_windows_debug_event (struct target_ops *ops, "EXCEPTION_DEBUG_EVENT")); if (saw_create != 1) break; - switch (handle_exception (ourstatus)) - { - case 0: - continue_status = DBG_EXCEPTION_NOT_HANDLED; - break; - case 1: - thread_id = current_event.dwThreadId; - break; - case -1: - last_sig = 1; - continue_status = -1; - break; - } + if (handle_exception (ourstatus)) + thread_id = current_event.dwThreadId; + else + continue_status = DBG_EXCEPTION_NOT_HANDLED; break; case OUTPUT_DEBUG_STRING_EVENT: /* Message from the kernel. */ @@ -1529,10 +1520,7 @@ get_windows_debug_event (struct target_ops *ops, if (!thread_id || saw_create != 1) { - if (continue_status == -1) - windows_resume (ops, minus_one_ptid, 0, 1); - else - CHECK (windows_continue (continue_status, -1, 0)); + CHECK (windows_continue (continue_status, -1, 0)); } else { -- 1.9.3