gdb/testsuite/gdb.threads/infcall-from-bp-cond-timeout.exp

# Copyright 2022-2025 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/>.

# Tests inferior calls executed from a breakpoint condition in
# a multi-threaded program.
#
# This test has the inferior function call timeout, and checks how GDB
# handles this situation.

standard_testfile

if { [build_executable "failed to prepare" ${binfile} "${srcfile}" \
	  {debug pthreads}] } {
    return
}

set cond_bp_line [gdb_get_line_number "Conditional breakpoint here"]
set final_bp_line [gdb_get_line_number "Stop marker"]
set segfault_line [gdb_get_line_number "Segfault here"]

# Setup GDB based on TARGET_ASYNC, TARGET_NON_STOP, and NON_STOP.
# Setup some breakpoints in the inferior, one of which has an inferior
# call within its condition.
#
# Continue GDB, the breakpoint with inferior call will be hit, but the
# inferior call will never return.  We expect GDB to timeout.
#
# The reason that the inferior call never completes is that a second
# thread, on which the inferior call relies, either hits a breakpoint
# (when OTHER_THREAD_BP is true), or crashes (when OTHER_THREAD_BP is
# false).
#
# When UNWIND is "on" GDB will unwind the thread which performed the
# inferior function call back to the state where the inferior call was
# made (when the inferior call times out).  Otherwise, when UNWIND is
# "off", the inferior is left in the frame where the timeout occurred.
proc run_test { target_async target_non_stop non_stop other_thread_bp unwind } {
    save_vars { ::GDBFLAGS } {
	append ::GDBFLAGS " -ex \"maint set target-non-stop $target_non_stop\""
	append ::GDBFLAGS " -ex \"maint non-stop $non_stop\""
	append ::GDBFLAGS " -ex \"maintenance set target-async ${target_async}\""

	clean_restart ${::testfile}
    }

    if {![runto_main]} {
	return
    }

    # The default timeout for indirect inferior calls (e.g. inferior
    # calls for conditional breakpoint expressions) is pretty high.
    # We don't want the test to take too long, so reduce this.
    #
    # However, the test relies on a second thread hitting some event
    # (either a breakpoint or signal) before this timeout expires.
    #
    # There is a chance that on a really slow system this might not
    # happen, in which case the test might fail.
    #
    # However, we still allocate 5 seconds, which feels like it should
    # be enough time in most cases, but maybe we need to do something
    # smarter here?  Possibly we could have some initial run where the
    # inferior doesn't timeout, but does perform the same interaction
    # between threads, we could time that, and use that as the basis
    # for this timeout.  For now though, we just hope 5 seconds is
    # enough.
    gdb_test_no_output "set indirect-call-timeout 5"
    gdb_test_no_output "set unwind-on-timeout $unwind"

    gdb_breakpoint \
	"${::srcfile}:${::cond_bp_line} if (condition_func ())"
    set bp_num [get_integer_valueof "\$bpnum" "*UNKNOWN*" \
		    "get number for conditional breakpoint"]

    gdb_breakpoint "${::srcfile}:${::final_bp_line}"
    set final_bp_num [get_integer_valueof "\$bpnum" "*UNKNOWN*" \
			  "get number for final breakpoint"]

    # The thread performing an inferior call relies on a second
    # thread.  The second thread will segfault unless it hits a
    # breakpoint first.  In either case the initial thread will not
    # complete its inferior call.
    if { $other_thread_bp } {
	gdb_breakpoint "${::srcfile}:${::segfault_line}"
	set segfault_bp_num [get_integer_valueof "\$bpnum" "*UNKNOWN*" \
				 "get number for segfault breakpoint"]
    }

    if { $unwind } {
	gdb_test "continue" \
	    [multi_line \
		 "Error in testing condition for breakpoint ${bp_num}:" \
		 "The program being debugged timed out while in a function called from GDB\\." \
		 "GDB has restored the context to what it was before the call\\." \
		 "To change this behavior use \"set unwind-on-timeout off\"\\." \
		 "Evaluation of the expression containing the function" \
		 "\\(condition_func\\) will be abandoned\\." \
		 "" \
		 "Thread ${::decimal}\[^\r\n\]*hit Breakpoint ${bp_num}, \[^\r\n\]+" \
		 "\[^\r\n\]+ Conditional breakpoint here\\. \[^\r\n\]+"] \
	    "expected timeout waiting for inferior call to complete"
    } else {
	# When non-stop mode is off we get slightly different output from GDB.
	if { ([target_info gdb_protocol] == "remote"
	      || [target_info gdb_protocol] == "extended-remote")
	     && !$target_non_stop} {
	    set stopped_line_pattern \
		"Thread ${::decimal} \"\[^\r\n\"\]+\" received signal SIGINT, Interrupt\\."
	} else {
	    set stopped_line_pattern "Thread ${::decimal} \"\[^\r\n\"\]+\" stopped\\."
	}

	gdb_test "continue" \
	    [multi_line \
		 "$stopped_line_pattern" \
		 ".*" \
		 "Error in testing condition for breakpoint ${bp_num}:" \
		 "The program being debugged timed out while in a function called from GDB\\." \
		 "GDB remains in the frame where the timeout occurred\\." \
		 "To change this behavior use \"set unwind-on-timeout on\"\\." \
		 "Evaluation of the expression containing the function" \
		 "\\(condition_func\\) will be abandoned\\." \
		 "When the function is done executing, GDB will silently stop\\."] \
	    "expected timeout waiting for inferior call to complete"
    }

    # Remember that other thread that either crashed (with a segfault)
    # or hit a breakpoint?  Now that the inferior call has timed out,
    # if we try to resume then we should see the pending event from
    # that other thread.
    if { $other_thread_bp } {
	gdb_test "continue" \
	    [multi_line \
		 "Continuing\\." \
		 ".*" \
		 "" \
		 "Thread ${::decimal} \"\[^\"\r\n\]+\" hit Breakpoint ${segfault_bp_num}, do_segfault \[^\r\n\]+:${::segfault_line}" \
		 "${::decimal}\\s+\[^\r\n\]+Segfault here\[^\r\n\]+"] \
	    "hit the segfault breakpoint"
    } else {
	gdb_test "continue" \
	    [multi_line \
		 "Continuing\\." \
		 ".*" \
		 "Thread ${::decimal} \"infcall-from-bp\" received signal SIGSEGV, Segmentation fault\\." \
		 "\\\[Switching to Thread \[^\r\n\]+\\\]" \
		 "${::hex} in do_segfault \\(\\) at \[^\r\n\]+:${::segfault_line}" \
		 "${::decimal}\\s+\[^\r\n\]+Segfault here\[^\r\n\]+"] \
	    "hit the segfault"
    }
}

foreach_with_prefix target_async {"on" "off" } {

    if { !$target_async } {
	# GDB can't timeout while waiting for a thread if the target
	# runs with async-mode turned off; once the target is running
	# GDB is effectively blocked until the target stops for some
	# reason.
	continue
    }

    foreach_with_prefix target_non_stop {"off" "on"} {
	foreach_with_prefix non_stop {"off" "on"} {
	    if { $non_stop && !$target_non_stop } {
		# It doesn't make sense to operate GDB in non-stop
		# mode when the target has (in theory) non-stop mode
		# disabled.
		continue
	    }
	    foreach_with_prefix unwind {"off" "on"} {
		foreach_with_prefix other_thread_bp { true false } {
		    run_test $target_async $target_non_stop $non_stop \
			$other_thread_bp $unwind
		}
	    }
	}
    }
}