Re: [PATCH] Fix random dejagnu test abort with simulator target

[Bernd Edlinger <bernd.edlinger@hotmail.de>]

On 4/19/24 15:26, Tom de Vries wrote:
> On 4/19/24 12:49, Bernd Edlinger wrote:
>> This is probably a dejagnu issue with the gdb testsuite
>> when a simulator target is used.  I observed random
>> testrun aborts with dejagnu 1.6.2-1 from ubuntu 20.04
>> The problem starts when the test case gdb.base/sigwinch-notty.exp
>> tries to execute "sleep", although that is impossible with a
>> simulator.  And for unknown reason the test case completes
>> (with errors) before the "after 1000" block is run.
>>
>> Then in a totally different test this happens with 50% likelihood:
>>
>> ERROR: (DejaGnu) proc "bgerror {can't read "gdb_pid": no such variable}" does not exist.
>> The error code is TCL LOOKUP COMMAND bgerror
>> The info on the error is:
>> invalid command name "bgerror"
>>      while executing
>> "::tcl_unknown bgerror {can't read "gdb_pid": no such variable}"
>>      ("uplevel" body line 1)
>>      invoked from within
>> "uplevel 1 ::tcl_unknown $args"
>>
>>                  === gdb Summary ===
>>
>>   # of expected passes            30815
>>   # of unexpected failures        241
>>   # of expected failures          3
>>   # of known failures             23
>>   # of unresolved testcases       241
>>   # of untested testcases         96
>>   # of unsupported tests          532
>>   # of paths in test names        1
>>
>> So the whole test run is aborted in the middle.
>>
>> This patch should fix the issue.
>> ---
>>   gdb/testsuite/gdb.base/sigwinch-notty.exp | 2 +-
>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/gdb/testsuite/gdb.base/sigwinch-notty.exp b/gdb/testsuite/gdb.base/sigwinch-notty.exp
>> index cef21c07c59..0f70f0978d2 100644
>> --- a/gdb/testsuite/gdb.base/sigwinch-notty.exp
>> +++ b/gdb/testsuite/gdb.base/sigwinch-notty.exp
>> @@ -21,7 +21,7 @@ require {!target_info exists gdb,nosignals}
>>     # The testfile relies on "run" from the command line, so only works
>>   # with "target native".
>> -if { [target_info gdb_protocol] != "" } {
>> +if { [target_info gdb_protocol] != "" || [target_info is_simulator] != ""} {
>>       return
>>   }
>>   
> 
> Hi Bernd,
> 
> thanks for the report and patch.
> 
> [ I ran the test-case using make-check-all.sh, and ran into trouble with host/target board local-remote-host-native.
> 
> I added some debugging here:
> ...
>  verbose -log "gdb_spawn_id=$gdb_spawn_id"
>  verbose -log "gdb_pid=$gdb_pid"
> +verbose -log "gdb_pid: [exec ps -p $gdb_pid]"
> ...
> and first ran with the default target board unix:
> ...
> gdb_spawn_id=exp6
> gdb_pid=28288
> gdb_pid:   PID TTY          TIME CMD
> 28288 pts/3    00:00:00 notty-wrap
> ...
> and then with host+target local-remote-host-native:
> ...
> gdb_spawn_id=exp6
> gdb_pid=27827
> gdb_pid:   PID TTY          TIME CMD
> 27827 pts/3    00:00:00 ssh
> ...
> 
> Which is basically the remote host variant of what's explained here for remote target:
> ...
> proc can_spawn_for_attach { } {
>     # We use exp_pid to get the inferior's pid, assuming that gives
>     # back the pid of the program.  On remote boards, that would give
>     # us instead the PID of e.g., the ssh client, etc.
>     if {[is_remote target]} {
>         verbose -log "can't spawn for attach (target is remote)"
>         return 0
>     }
> ...
> 
> Anyway, this can be fixed using:
> ...
> -if { [target_info gdb_protocol] != "" } {
> +if { [target_info gdb_protocol] != "" || [is_remote host] } {
> ...
> ]
> 
> Back to the problem you reported.
> 
> I wonder about using gdb_spawn without checking for the result.  Does it still reproduce if we bail out when gdb_spawn fails?
> 

> If so, can you show the actual gdb.log for the test-case?
> 

Sure,

testcase /home/ed/gnu/binutils-build-riscv-1/gdb/testsuite/../../../binutils-gdb/gdb/testsuite/gdb.base/sigstep.exp completed in 0 seconds
Running /home/ed/gnu/binutils-build-riscv-1/gdb/testsuite/../../../binutils-gdb/gdb/testsuite/gdb.base/sigwinch-notty.exp ...
Executing on build: rm -rf /home/ed/gnu/binutils-build-riscv-1/gdb/testsuite/outputs/gdb.base/sigwinch-notty    (timeout = 300)
builtin_spawn -ignore SIGHUP rm -rf /home/ed/gnu/binutils-build-riscv-1/gdb/testsuite/outputs/gdb.base/sigwinch-notty^M
builtin_spawn /home/ed/gnu/binutils-build-riscv-1/gdb/testsuite/../../../binutils-gdb/gdb/testsuite/lib/notty-wrap /home/ed/gnu/binutils-build-riscv-1/gdb/testsuite/../../gdb/gdb -nw -nx -q -iex set height 0 -iex set width 0 -data-directory /home/ed/gnu/binutils-build-riscv-1/gdb/data-directory -ex show editing -ex run --args sleep 3^M
gdb_spawn_id=exp9
gdb_pid=79294
^M
warning: A handler for the OS ABI "GNU/Linux" is not built into this configuration^M
of GDB.  Attempting to continue with the default riscv settings.^M
^M
Reading symbols from sleep...^M
(No debugging symbols found in sleep)^M
Editing of command lines as they are typed is off.^M
Don't know how to run.  Try "help target".^M
(gdb) FAIL: gdb.base/sigwinch-notty.exp: wait for sleep exit
GDB process exited with wait status 79294 exp9 0 0
PASS: gdb.base/sigwinch-notty.exp: wait for gdb exit
testcase /home/ed/gnu/binutils-build-riscv-1/gdb/testsuite/../../../binutils-gdb/gdb/testsuite/gdb.base/sigwinch-notty.exp completed in 0 seconds
Running /home/ed/gnu/binutils-build-riscv-1/gdb/testsuite/../../../binutils-gdb/gdb/testsuite/gdb.base/sizeof.exp ...
Executing on build: rm -rf /home/ed/gnu/binutils-build-riscv-1/gdb/testsuite/outputs/gdb.base/sizeof    (timeout = 300)
builtin_spawn -ignore SIGHUP rm -rf /home/ed/gnu/binutils-build-riscv-1/gdb/testsuite/outputs/gdb.base/sizeof^M
Executing on host: riscv-unknown-elf-gcc  -fno-stack-protector  -fdiagnostics-color=never -c   -g  -o /home/ed/gnu/binutils-build-riscv-1/gdb/testsuite/outputs/gdb.base/sizeof/sizeof0.o /home/ed/gnu/binutils-build-riscv-1/gdb/testsuite/../../../binutils-gdb/gdb/testsuite/gdb.base/sizeof.c    (timeout = 300)
builtin_spawn -ignore SIGHUP riscv-unknown-elf-gcc -fno-stack-protector -fdiagnostics-color=never -c -g -o /home/ed/gnu/binutils-build-riscv-1/gdb/testsuite/outputs/gdb.base/sizeof/sizeof0.o /home/ed/gnu/binutils-build-riscv-1/gdb/testsuite/../../../binutils-gdb/gdb/testsuite/gdb.base/sizeof.c^M

[and a few 1000 lines later]

uiltin_spawn -ignore SIGHUP rm -rf /home/ed/gnu/binutils-build-riscv-1/gdb/testsuite/outputs/gdb.base/so-impl-ld^M
UNSUPPORTED: gdb.base/so-impl-ld.exp: require failed: allow_shlib_tests
testcase /home/ed/gnu/binutils-build-riscv-1/gdb/testsuite/../../../binutils-gdb/gdb/testsuite/gdb.base/so-impl-ld.exp completed in 0 seconds
Running /home/ed/gnu/binutils-build-riscv-1/gdb/testsuite/../../../binutils-gdb/gdb/testsuite/gdb.base/solib-abort.exp ...
Executing on build: rm -rf /home/ed/gnu/binutils-build-riscv-1/gdb/testsuite/outputs/gdb.base/solib-abort    (timeout = 300)
builtin_spawn -ignore SIGHUP rm -rf /home/ed/gnu/binutils-build-riscv-1/gdb/testsuite/outputs/gdb.base/solib-abort^M
ERROR: (DejaGnu) proc "bgerror {can't read "gdb_pid": no such variable}" does not exist.
The error code is TCL LOOKUP COMMAND bgerror
The info on the error is:
invalid command name "bgerror"
    while executing
"::tcl_unknown bgerror {can't read "gdb_pid": no such variable}"
    ("uplevel" body line 1)
    invoked from within
"uplevel 1 ::tcl_unknown $args"

                === gdb Summary ===

# of expected passes            30817
# of unexpected failures        241
# of expected failures          3
# of known failures             23
# of unresolved testcases       241
# of untested testcases         96
# of unsupported tests          527
# of paths in test names        1
Executing on host: /home/ed/gnu/binutils-build-riscv-1/gdb/testsuite/../../gdb/gdb -nw -nx -q -iex "set height 0" -iex "set width 0" -data-directory /home/ed/gnu/binutils-build-riscv-1/gdb/data-directory --version    (timeout = 300)
builtin_spawn -ignore SIGHUP /home/ed/gnu/binutils-build-riscv-1/gdb/testsuite/../../gdb/gdb -nw -nx -q -iex set height 0 -iex set width 0 -data-directory /home/ed/gnu/binutils-build-riscv-1/gdb/data-directory --version^M
GNU gdb (GDB) 15.0.50.20240419-git^M
Copyright (C) 2024 Free Software Foundation, Inc.^M
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>^M
This is free software: you are free to change and redistribute it.^M
There is NO WARRANTY, to the extent permitted by law.^M
/home/ed/gnu/binutils-build-riscv-1/gdb/gdb version  15.0.50.20240419-git -nw -nx -q -iex "set height 0" -iex "set width 0" -data-directory /home/ed/gnu/binutils-build-riscv-1/gdb/data-directory

looks like this is the spawned gdb?

Thanks
Bernd.