1# This testcase is part of GDB, the GNU debugger. 2# 3# Copyright 2013-2020 Free Software Foundation, Inc. 4# 5# This program is free software; you can redistribute it and/or modify 6# it under the terms of the GNU General Public License as published by 7# the Free Software Foundation; either version 3 of the License, or 8# (at your option) any later version. 9# 10# This program is distributed in the hope that it will be useful, 11# but WITHOUT ANY WARRANTY; without even the implied warranty of 12# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13# GNU General Public License for more details. 14# 15# You should have received a copy of the GNU General Public License 16# along with this program. If not, see <http://www.gnu.org/licenses/>. 17 18# Regression test for a bug that would go like this: 19# 20# - Run to a breakpoint that is hit by two threads (A and B) 21# simultaneously. 22# 23# - One of the breakpoint hits is processed (e.g., thread A) and 24# causes a user-visible stop. The other (thread B) is left pending. 25# 26# - The user deletes the breakpoint with "del", which causes a 27# confirmation query. 28# 29# - By mistake, that would result in the target being left with async 30# enabled, even though it wasn't to begin with. 31# 32# - GDB reacts to target async enablement by polling for target 33# events. As no thread is resumed the target replies 34# TARGET_WAITKIND_NO_RESUMED. 35# 36# - The user continues the program, expecting it to exit. The thread 37# that has an event pending (thread B) is not really resumed. 38# 39# - But, nothing signals the event loop that there's a pending event 40# waiting to be collected for thread B, so that event is never 41# processed, thread B is never resumed and the program never exits. 42# 43# Ref: https://sourceware.org/ml/gdb-patches/2015-01/msg00592.html 44 45standard_testfile 46 47if {[prepare_for_testing "failed to prepare" $testfile $srcfile {debug pthreads}] == -1} { 48 return -1 49} 50 51proc test {} { 52 global srcfile gdb_prompt 53 54 if ![runto_main] { 55 return -1 56 } 57 58 delete_breakpoints 59 60 set bp_line [gdb_get_line_number "set break here" $srcfile] 61 62 gdb_breakpoint "break_function" 63 gdb_continue_to_breakpoint "cont to break_function" ".*$srcfile:$bp_line\r\n.*" 64 65 # Do something that causes a query/secondary prompt. 66 67 set test "delete breakpoints, answer prompt" 68 set saw_prompt 0 69 gdb_test_multiple "delete breakpoints" $test { 70 -re "Delete all breakpoints.*y or n.*$" { 71 set saw_prompt 1 72 send_gdb "y\n" 73 exp_continue 74 } 75 -re "$gdb_prompt $" { 76 gdb_assert $saw_prompt $test 77 } 78 } 79 80 gdb_continue_to_end "" "continue" 1 81} 82 83# Test a few times to make sure an event is left pending. At the time 84# of writing, the bug always triggers, but that might naturally depend 85# on machine. 86for {set i 1} {$i <= 10} {incr i} { 87 with_test_prefix "iter $i" { 88 test 89 } 90} 91