gdb/testsuite/gdb.threads/signal-while-stepping-over-bp-other-thread.exp

# Copyright (C) 2011-2021 Free Software Foundation, Inc.

# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

# Test that GDB doesn't inadvertently resume the stepped thread when a
# signal arrives while stepping over the breakpoint that last caused a
# stop, when the thread that hit that breakpoint is not the stepped
# thread.

# Test relies on checking gdb debug output. Do not run if gdb debug is
# enabled as any debug will be redirected to the log.
if [gdb_debug_enabled] {
    continue
}

standard_testfile
set executable ${testfile}

if [target_info exists gdb,nosignals] {
    verbose "Skipping ${testfile}.exp because of nosignals."
    return -1
}

if {[gdb_compile_pthreads "${srcdir}/${subdir}/${srcfile}" "${binfile}" \
	 executable [list debug "incdir=${objdir}"]] != "" } {
    return -1
}

proc get_value {var test} {
    global expect_out
    global gdb_prompt
    global decimal

    set value -1
    gdb_test_multiple "print $var" "$test" {
	-re ".*= ($decimal).*\r\n$gdb_prompt $" {
	    set value $expect_out(1,string)
	    pass "$test"
        }
    }
    return ${value}
}

# Start with a fresh gdb.

clean_restart $executable

if ![runto_main] {
    return -1
}

gdb_breakpoint [gdb_get_line_number "set wait-thread-2 breakpoint here"]
gdb_continue_to_breakpoint "run to wait-thread-2 breakpoint"
gdb_test "info threads" "" "info threads with thread 2"

gdb_breakpoint [gdb_get_line_number "set wait-thread-3 breakpoint here"]
gdb_continue_to_breakpoint "run to breakpoint"
gdb_test "info threads" "" "info threads with thread 3"

gdb_test "set scheduler-locking on"

gdb_breakpoint [gdb_get_line_number "set breakpoint child_two here"]
gdb_breakpoint [gdb_get_line_number "set breakpoint child_one here"]

gdb_test "thread 3" "" "switch to thread 3 to run to its breakpoint"
gdb_continue_to_breakpoint "run to breakpoint in thread 3"

gdb_test "thread 2" "" "switch to thread 2 to run to its breakpoint"
gdb_continue_to_breakpoint "run to breakpoint in thread 2"

delete_breakpoints

gdb_test "b *\$pc" "" "set breakpoint to be stepped over"
# Make sure the first loop breaks without hitting the breakpoint
# again.
gdb_test "p *myp = 0" " = 0" "force loop break in thread 2"

# We want "print" to make sure the target reports the signal to the
# core.
gdb_test "handle SIGUSR1 print nostop pass" "" ""

gdb_test "thread 1" "" "switch to thread 1 to queue signal in thread 2"
gdb_test "next 2" "pthread_join .*" "queue signal in thread 2"

gdb_test "thread 3" "" "switch to thread 3 for stepping"
set my_number [get_value "my_number" "get my_number"]
set cnt_before [get_value "args\[$my_number\]" "get count before step"]
gdb_test "set scheduler-locking off"

# Make sure we're exercising the paths we want to.
gdb_test "set debug infrun 1"

set test "step"
gdb_test_sequence $test $test -prompt "$gdb_prompt \\\[infrun\\\] fetch_inferior_event: exit\r\n$"  {
    "need to step-over"
    "resume_1: step=1,"
    "signal arrived while stepping over breakpoint"
    "stepped to a different line"
    "callme"
}

set cnt_after [get_value "args\[$my_number\]" "get count after step"]

# Test that GDB doesn't inadvertently resume the stepped thread when a
# signal arrives while stepping over a breakpoint in another thread.

gdb_assert { $cnt_before + 1 == $cnt_after } "stepped thread under control"