Re: [PATCH 04/14] gdb/testsuite: Avoid fake failures when exit is unreliable

[Shahab Vahedi <Shahab dot Vahedi at synopsys dot com>]

On 2/11/20 9:10 AM, Luis Machado wrote:
> Hi,
> 
> On 2/7/20 11:59 AM, Shahab Vahedi wrote:
>> From: Anton Kolesov <Anton.Kolesov@synopsys.com>
>>
>> Tests that run in background will not run properly with targets that
>> doesn't have a proper "exit" function. For example, gdb.base/hook-stop
>> expects that after hook will resume inferior in background, there would
>> be a message "exited normally", however such a message will appear only
>> for targets with a proper exit(), while others will, for example, spin
>> in the infinite loop.
>>
>> Test gdb.base/nextoverexit expects message "inferior exited normally",
>> which is present only when exit() actually halts the target.
>>
>> Some tests in gdb.base/commands.exp has a flow that expects that
>> application can exit itself, which is not true when exit() function is
>> not reliable.
>>
>> This patch makes those tests conditional - they run only if exit is
>> reliable.
> 
> I don't know about this one. Doesn't your debugging stub have a way of detecting a call to exit, for example?

There is some testglue (gdb_tg.o) that prints to stdout if exit has happened with values other than 0. However, I believe the issue here is about running on a board. Anton is the best for responding to this.

> 
> These changes seem to indicate you are using some custom/modified dejagnu board to run your tests. Is your target a qemu/probe that gdb connects to and then does the tests?
That is correct. The target has never been qemu/probe. I believe it has been the in-house simulator and also some real boards.

> 
>>
>> gdb/testsuite/ChangeLog:
>> 2016-07-13  Anton Kolesov <Anton.Kolesov@synopsys.com>
>>
>>     * gdb.base/callexit.exp: Expect an "exit()" only if
>>     "exit_is_reliable" says so.
>>     * gdb.base/commands.exp: Likewise.
>>     * gdb.base/ena-dis-br.exp: Likewise.
>>     * gdb.base/hook-stop.exp: Likewise.
>>     * gdb.base/nextoverexit.exp: Likewise.
>>     * gdb.mi/mi-break.exp: Likewise.
>>     * gdb.mi/mi-exit-code.exp: Likewise.
>>     * gdb.mi/mi-simplerun.exp: Likewise.
>>
>> Signed-off-by: Anton Kolesov <Anton.Kolesov@synopsys.com>
>> ---
>>   gdb/testsuite/gdb.base/callexit.exp     |  7 +++++++
>>   gdb/testsuite/gdb.base/commands.exp     | 14 ++++++++++++++
>>   gdb/testsuite/gdb.base/ena-dis-br.exp   | 18 +++++++++++-------
>>   gdb/testsuite/gdb.base/hook-stop.exp    | 12 +++++++++++-
>>   gdb/testsuite/gdb.base/nextoverexit.exp |  7 +++++++
>>   gdb/testsuite/gdb.mi/mi-break.exp       |  5 +++++
>>   gdb/testsuite/gdb.mi/mi-exit-code.exp   |  5 +++++
>>   gdb/testsuite/gdb.mi/mi-simplerun.exp   |  5 +++++
>>   8 files changed, 65 insertions(+), 8 deletions(-)
>>
>> diff --git a/gdb/testsuite/gdb.base/callexit.exp b/gdb/testsuite/gdb.base/callexit.exp
>> index 67ff48283646..4fc2d5a2669a 100644
>> --- a/gdb/testsuite/gdb.base/callexit.exp
>> +++ b/gdb/testsuite/gdb.base/callexit.exp
>> @@ -28,6 +28,13 @@ if [target_info exists gdb,cannot_call_functions] {
>>       continue
>>   }
>>   +# Some targets (for example baremetal ones) doesn't have exit() that actually
>> +# exits anywhere.
>> +if ![exit_is_reliable] {
>> +    unsupported "This target doesn't have reliable exit() function."
>> +    continue
>> +}
>> +
>>   # Start with a fresh gdb.
>>     clean_restart ${binfile}
>> diff --git a/gdb/testsuite/gdb.base/commands.exp b/gdb/testsuite/gdb.base/commands.exp
>> index 869d0a81a4a7..fd92b3fa3111 100644
>> --- a/gdb/testsuite/gdb.base/commands.exp
>> +++ b/gdb/testsuite/gdb.base/commands.exp
>> @@ -694,6 +694,13 @@ proc_with_prefix deprecated_command_test {} {
>>   proc_with_prefix bp_deleted_in_command_test {} {
>>       global gdb_prompt
>>   +    # Flow of this test assumes that application will halt after reaching the
>> +    # exit() function.
>> +    if ![exit_is_reliable] {
>> +    unsupported "Function exit() is not reliable on this board."
>> +    return 0
>> +    }
>> +
>>       delete_breakpoints
>>         # Create a breakpoint, and associate a command-list to it, with
>> @@ -736,6 +743,13 @@ proc_with_prefix bp_deleted_in_command_test {} {
>>   }
>>     proc_with_prefix temporary_breakpoint_commands {} {
>> +    # Flow of this test assumes that application will halt after reaching the
>> +    # exit() function.
>> +    if ![exit_is_reliable] {
>> +    unsupported "Function exit() is not reliable on this board."
>> +    return 0
>> +    }
>> +
>>       delete_breakpoints
>>         # Create a temporary breakpoint, and associate a commands list to it.
>> diff --git a/gdb/testsuite/gdb.base/ena-dis-br.exp b/gdb/testsuite/gdb.base/ena-dis-br.exp
>> index c338a0d51fa9..bf670cbae948 100644
>> --- a/gdb/testsuite/gdb.base/ena-dis-br.exp
>> +++ b/gdb/testsuite/gdb.base/ena-dis-br.exp
>> @@ -295,13 +295,17 @@ gdb_test "continue 2" \
>>   gdb_test "next" ".*$bp_location11\[ \t\]*marker1.*" \
>>       "step after continue with ignore count"
>>   -set test "continue with ignore count, not stopped at bpt"
>> -gdb_test_multiple "continue 2" "$test" {
>> -    -re "Not stopped at any breakpoint; argument ignored.*$gdb_prompt $" {
>> -    pass "$test"
>> -    }
>> -    -re "No breakpoint number -1.*$gdb_prompt $" {
>> -    kfail gdb/1689 "$test"
>> +# Application is expected to reach an exit() here, so this can't be run if exit
>> +# is not working.
>> +if [exit_is_reliable] {
>> +    set test "continue with ignore count, not stopped at bpt"
>> +    gdb_test_multiple "continue 2" "$test" {
>> +    -re "Not stopped at any breakpoint; argument ignored.*$gdb_prompt $" {
>> +        pass "$test"
>> +    }
>> +    -re "No breakpoint number -1.*$gdb_prompt $" {
>> +        kfail gdb/1689 "$test"
>> +    }
>>       }
>>   }
>>   diff --git a/gdb/testsuite/gdb.base/hook-stop.exp b/gdb/testsuite/gdb.base/hook-stop.exp
>> index 6b49e39b7380..c9bc3d3b6438 100644
>> --- a/gdb/testsuite/gdb.base/hook-stop.exp
>> +++ b/gdb/testsuite/gdb.base/hook-stop.exp
>> @@ -165,5 +165,15 @@ proc hook_stop_next {} {
>>   hook_stop_before_frame
>>   hook_stop_kill
>>   hook_stop_continue_fg
>> -hook_stop_continue_bg
>> +
>> +# Tests that run in background will not run properly with targets that
>> +# doesn't have a proper "exit" function. For example, this particular
>> +# test expects that after hook will resume inferior in background, there
>> +# would be a message "exited normally", however such a message will
>> +# appear only for targets with a proper # exit(), while others will, for
>> +# example, spin in the infinite loop.
>> +if [exit_is_reliable] {
>> +    hook_stop_continue_bg
>> +}
>> +
>>   hook_stop_next
>> diff --git a/gdb/testsuite/gdb.base/nextoverexit.exp b/gdb/testsuite/gdb.base/nextoverexit.exp
>> index 30eafef675ff..fcea35762b00 100644
>> --- a/gdb/testsuite/gdb.base/nextoverexit.exp
>> +++ b/gdb/testsuite/gdb.base/nextoverexit.exp
>> @@ -14,6 +14,13 @@
>>     standard_testfile
>>   +# This tests expects message "inferior exited normally", which is present only
>> +# when exit() actually halts the target.
>> +if ![exit_is_reliable] {
>> +    unsupported "Function exit() is not reliable on this board."
>> +    return 0
>> +}
>> +
>>   if {[prepare_for_testing "failed to prepare" $testfile $testfile.c]} {
>>       return -1
>>   }
>> diff --git a/gdb/testsuite/gdb.mi/mi-break.exp b/gdb/testsuite/gdb.mi/mi-break.exp
>> index 1149bb34c8dc..acec246f52ee 100644
>> --- a/gdb/testsuite/gdb.mi/mi-break.exp
>> +++ b/gdb/testsuite/gdb.mi/mi-break.exp
>> @@ -244,6 +244,11 @@ proc test_disabled_creation {} {
>>   proc test_breakpoint_commands {} {
>>       global line_callee2_body
>>   +    if ![exit_is_reliable] {
>> +    unsupported "This test requires working exit() function."
>> +    return 0
>> +    }
>> +
>>       set bp_no_script \
>>       [mi_create_breakpoint "basics.c:callee2" \
>>            "breakpoint commands: insert breakpoint at basics.c:callee2" \
>> diff --git a/gdb/testsuite/gdb.mi/mi-exit-code.exp b/gdb/testsuite/gdb.mi/mi-exit-code.exp
>> index f10b49cee0f8..fb5c693597da 100644
>> --- a/gdb/testsuite/gdb.mi/mi-exit-code.exp
>> +++ b/gdb/testsuite/gdb.mi/mi-exit-code.exp
>> @@ -23,6 +23,11 @@ if [mi_gdb_start] {
>>     standard_testfile
>>   +if ![exit_is_reliable] {
>> +    unsupported "Function exit() is not reliable on this board."
>> +    return 0
>> +}
>> +
>>   if { [gdb_compile "${srcdir}/${subdir}/${srcfile}" "${binfile}" executable {debug}] != "" } {
>>       untested "failed to compile"
>>       return -1
>> diff --git a/gdb/testsuite/gdb.mi/mi-simplerun.exp b/gdb/testsuite/gdb.mi/mi-simplerun.exp
>> index 20a079ead896..ce19122803da 100644
>> --- a/gdb/testsuite/gdb.mi/mi-simplerun.exp
>> +++ b/gdb/testsuite/gdb.mi/mi-simplerun.exp
>> @@ -177,6 +177,11 @@ proc test_program_termination {} {
>>       # -exec-abort
>>       # (normal termination of inferior)
>>   +    if ![exit_is_reliable] {
>> +    unsupported "Function exit() is not reliable on this board."
>> +    return
>> +    }
>> +
>>       mi_execute_to "exec-continue" "exited-normally" "" "" "" "" "" "continue to end"
>>   }
>>