From 95824559df96a53ddeccbaacd91617f83c8d52cd Mon Sep 17 00:00:00 2001 From: Pedro Alves Date: Tue, 17 Nov 2015 15:17:45 +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: 2015-11-17 Pedro Alves * windows-nat.c (handle_exception): Return 0 for first chance exceptions. (get_windows_debug_event): Adjust. --- gdb/ChangeLog | 6 ++++++ gdb/windows-nat.c | 24 ++++++------------------ 2 files changed, 12 insertions(+), 18 deletions(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 4639df4..fbfe4ad 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,5 +1,11 @@ 2015-11-17 Pedro Alves + * windows-nat.c (handle_exception): Return 0 for first chance + exceptions. + (get_windows_debug_event): Adjust. + +2015-11-17 Pedro Alves + * windows-nat.c (xslate): Use GDB_SIGNAL_UNKNOWN instead of -1 as signal number for terminator. 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 { -- 2.7.4