1# Copyright (C) 2014-2020 Free Software Foundation, Inc. 2 3# This program is free software; you can redistribute it and/or modify 4# it under the terms of the GNU General Public License as published by 5# the Free Software Foundation; either version 3 of the License, or 6# (at your option) any later version. 7# 8# This program is distributed in the hope that it will be useful, 9# but WITHOUT ANY WARRANTY; without even the implied warranty of 10# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 11# GNU General Public License for more details. 12# 13# You should have received a copy of the GNU General Public License 14# along with this program. If not, see <http://www.gnu.org/licenses/>. 15 16# On decr_pc_after_break targets, GDB used to adjust the PC 17# incorrectly if a background single-step stopped somewhere where 18# PC-$decr_pc had a breakpoint, and the thread was not the current 19# thread, like: 20# 21# ADDR1 nop <-- breakpoint here 22# ADDR2 jmp PC 23# 24# IOW, say thread A is stepping ADDR2's line in the background (an 25# infinite loop), and the user switches focus to thread B. GDB's 26# adjust_pc_after_break logic would confuse the single-step stop of 27# thread A for a hit of the breakpoint at ADDR1, and thus adjust 28# thread A's PC to point at ADDR1 when it should not: the thread had 29# been single-stepped, not continued. 30 31standard_testfile 32 33if {[prepare_for_testing "failed to prepare" $testfile $srcfile {debug pthreads}] == -1} { 34 return -1 35} 36 37clean_restart $binfile 38 39if ![runto_main] { 40 continue 41} 42 43# Make sure it's GDB's decr_pc logic that's being tested, not the 44# target's. 45gdb_test_no_output "set range-stepping off" 46 47delete_breakpoints 48 49gdb_breakpoint [gdb_get_line_number "set breakpoint here"] 50gdb_continue_to_breakpoint "run to nop breakpoint" 51gdb_test "info threads" " 1 .*\\\* 2 .*" "info threads shows all threads" 52 53gdb_test "next" "while.*" "next over nop" 54 55gdb_test_no_output "next&" "next& over inf loop" 56 57set test "switch to main thread" 58gdb_test_multiple "thread 1" $test { 59 -re "Cannot execute this command while the target is running.*$gdb_prompt $" { 60 unsupported $test 61 62 # With remote targets, we can't send any other remote packet 63 # until the target stops. Switching thread wants to ask the 64 # remote side whether the thread is alive. 65 return 66 } 67 -re "Switching to thread 1.*\\(running\\)\r\n$gdb_prompt " { 68 # Prefer to match the prompt without an anchor. If there's a 69 # bug and output comes after the prompt immediately, it's 70 # faster to handle that in the following test, instead of 71 # waiting for a timeout here. 72 pass $test 73 } 74} 75 76# Wait a bit. Use gdb_expect instead of sleep so that any (bad) GDB 77# output is visible in the log. 78gdb_expect 4 {} 79 80set test "no output while stepping" 81gdb_test_multiple "" $test { 82 -timeout 1 83 timeout { 84 pass $test 85 } 86 -re "." { 87 # If we see any output, it's a failure. On the original bug, 88 # this would be a breakpoint hit. 89 fail $test 90 } 91} 92