No stacktrace is printed on Segfault

[firesurfer]

Hi, I am look for some help how to integrate this package.

System

Ubuntu 22.04
Ros2 Iron
backward_ros: 1.0.5

Setup

I added <depend>backward_ros</depend> to my package.xml.
And find_package(backward_ros REQUIRED)

Additionally I set target_compile_options(my_node PRIVATE "-g") just to make sure that it compiles with debug information.

Unfortunately this doesn't work. I tried the advice from #13 to include find_package(Backward) but that still doesn't work.

This is the output of cmake:

-- BACKWARD_HAS_UNWIND=1
-- BACKWARD_HAS_BACKTRACE=0
-- BACKWARD_HAS_BACKTRACE_SYMBOL=0
-- BACKWARD_HAS_DW=1
-- BACKWARD_HAS_BFD=0
-- Found Backward: /opt/ros/iron/share/backward_ros/cmake  

@christophfroehlich I realized a while ago that also the controller_manager does not print stacktraces anymore. So it might that a dependency has changed, or my system is broken ?

[christophfroehlich]

I see stacktraces all around ;) Have you made a clean build after adding backward?

[firesurfer]

Yes I did. I just tried again in a clean container environment and still: no backtraces.

For testing purposes I added some lines that produce a segfault.

[christophfroehlich]

I have RelWithDebInfo in my colcon defaults. Maybe you can try that instead of the compile options flag.

[firesurfer]

I also tried that but it didn't work. I have the feeling it something about the backward_ros package in iron.

What I did now is follow the guide the backward_cpp package: https://github.com/bombela/backward-cpp and directly include it via FetchContent.

[ottojo]

Hi! I also don't seem to have stacktraces anymore when using this package, maybe some system dependency broke in the past months?

I pushed a ros node here which is just the default from ros2 pkg create... and an invalid pointer dereference in the main function.

Some version information:

ros-iron-backward-ros is already the newest version (1.0.5-1jammy.20240711.224901).
Ubuntu 22.04.5 LTS
Linux ade 5.15.0-122-generic #132~20.04.1-Ubuntu SMP Fri Aug 30 15:50:07 UTC 2024 x86_64 x86_64 x86_64 GNU/Linux
c++ (Ubuntu 11.4.0-1ubuntu1~22.04) 11.4.0

from compile_commands.json:

/usr/bin/c++  -I/home/jonasotto/workspace/ros2_ws/src/segfault_node/include -I/opt/ros/iron/include -Werror=uninitialized -Werror=maybe-uninitialized -Werror=return-type -Wreorder -B/usr/libexec/mold -g -Wall -Wextra -Wpedantic -o CMakeFiles/segfault_node.dir/src/segfault_node.cpp.o -c /home/jonasotto/workspace/ros2_ws/src/segfault_node/src/segfault_node.cpp

from cmake link.txt:

/usr/bin/c++ -Werror=uninitialized -Werror=maybe-uninitialized -Werror=return-type -Wreorder -g CMakeFiles/segfault_node.dir/src/segfault_node.cpp.o -o segfault_node  -Wl,-rpath,/opt/ros/iron/lib /opt/ros/iron/lib/libbackward.so 

Edit: While this is the case in iron, the backtrace is produced as expected in jazzy...

[firesurfer]

Hi @ottojo if you need the stacktrace in iron. This is how I managed to get one:
bombela/backward-cpp#341

[saikishor]

Hi! I also don't seem to have stacktraces anymore when using this package, maybe some system dependency broke in the past months?

I pushed a ros node here which is just the default from ros2 pkg create... and an invalid pointer dereference in the main function.

Edit: While this is the case in iron, the backtrace is produced as expected in jazzy...

Hello @ottojo!

We have found a small issue and we are on the way to fix it. Probably, today you should have it. I'll make releases to have it in Iron before it's EOL

[saikishor]

Hello All!

The issue is fixed and released to all ROS 2 Distros. Sorry for not getting back to it earlier. I'll go ahead and close this issue for now. If the issue persists feel free to open a new issue or reopen this one.
ros/rosdistro#43375 ros/rosdistro#43376 ros/rosdistro#43377 ros/rosdistro#43378

Thank you,

Best Regards,
PAL Robotics Team.