ROS2 Humble Support, Compilation

[xcodian]

Hey! I was hoping to integrate your work into the build pipeline of a autonomous robotics research project at The University of New South Wales, but I am currently unable to compile your code to even test it out.

ROS2 Humble is the stable release of ROS2 supported until 2027 (2 years earlier than Jazzy),
and is very commonly used in production.

Trying to rosdep install on humble,

$ rosdep install --from-paths src/rosidlcpp --ignore-src
ERROR: the following packages/stacks could not have their rosdep keys resolved
to system dependencies:
rosidlcpp_generator_c: Cannot locate rosdep definition for [rosidl_generator_type_description]
rosidlcpp_generator_py: Cannot locate rosdep definition for [rosidl_pycommon]
rosidlcpp_generator_cpp: Cannot locate rosdep definition for [rosidl_generator_type_description]
rosidlcpp_typesupport_c: Cannot locate rosdep definition for [rosidl_pycommon]
rosidlcpp_typesupport_cpp: Cannot locate rosdep definition for [rosidl_pycommon]
rosidlcpp_typesupport_introspection_cpp: Cannot locate rosdep definition for [rosidl_pycommon]
rosidlcpp_typesupport_introspection_c: Cannot locate rosdep definition for [rosidl_pycommon]

My development environment made up of "not-so-latest" versions of tools:

$ echo $ROS_DISTRO
humble

$ echo $ROS_VERSION 
2

$ cat /etc/os-release 
PRETTY_NAME="Ubuntu 22.04.5 LTS"
NAME="Ubuntu"
VERSION_ID="22.04"
VERSION="22.04.5 LTS (Jammy Jellyfish)"
VERSION_CODENAME=jammy
ID=ubuntu
ID_LIKE=debian
HOME_URL="https://www.ubuntu.com/"
SUPPORT_URL="https://help.ubuntu.com/"
BUG_REPORT_URL="https://bugs.launchpad.net/ubuntu/"
PRIVACY_POLICY_URL="https://www.ubuntu.com/legal/terms-and-policies/privacy-policy"
UBUNTU_CODENAME=jammy

$ g++ --version
g++ (Ubuntu 11.4.0-1ubuntu1~22.04) 11.4.0
Copyright (C) 2021 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

$ python3 --version
Python 3.10.12

Hoping you could shed light on how I can get your code to compile and run.

Additionally, I would appreciate it if you shared your compiler toolchain version. Even though g++ 11.4 supports -std=c++23, it seems like some of the newest headers out there such as <format> are still sparsely supported, and equivalent but more widely supported alternatives exist, such as fmtlib.

My goal is to try out your project on the environment shared above. Many thanks for your work thus far!

[TonyWelte]

Hey! It's great to hear that someone is trying to use this.

For the dependencies, you should be able to ignore the missing ones, as some are no longer needed and others didn't exist on Humble. You can do this by running:

rosdep install --from-paths src/rosidlcpp --ignore-src -r

I originally started this project to experiment with newer C++ features, so it requires a recent compiler version. I developed it on Ubuntu 24.04 with gcc 13.3. After some tinkering, I managed to get everything to compile on Humble with Ubuntu 22.04 (see the experimental/humble branch). However, there are still some issues. Building a package with it fails, and it seems that the _generate_interfaces.cmake files have changed since Humble.

Even if you manage to get it working on Humble, there is no guarantee that the generated files will be compatible. Several rosidl generators and runtimes have gone up a major version, and fastcdr was also bumped to version 2.

[rty813]

root@rk3568 ~/ws# colcon build 
Starting >>> interfaces
--- stderr: interfaces                           
CMake Error at /opt/ros/humble/share/rosidl_cmake/cmake/rosidl_write_generator_arguments.cmake:44 (message):
  rosidl_write_generator_arguments() called with unused arguments:
  INCLUDE_PATHS;std_msgs:/opt/ros/humble/share/std_msgs;builtin_interfaces:/opt/ros/humble/share/builtin_interfaces;sensor_msgs:/opt/ros/humble/share/sensor_msgs;geometry_msgs:/opt/ros/humble/share/geometry_msgs
Call Stack (most recent call first):
  /root/ros/install/rosidlcpp_generator_type_description/share/rosidlcpp_generator_type_description/cmake/rosidlcpp_generator_type_description_generate_interfaces.cmake:72 (rosidl_write_generator_arguments)
  /opt/ros/humble/share/ament_cmake_core/cmake/core/ament_execute_extensions.cmake:48 (include)
  /opt/ros/humble/share/rosidl_cmake/cmake/rosidl_generate_interfaces.cmake:286 (ament_execute_extensions)
  CMakeLists.txt:14 (rosidl_generate_interfaces)


---
Failed   <<< interfaces [11.5s, exited with code 1]

Summary: 0 packages finished [13.1s]
  1 package failed: interfaces
  1 package had stderr output: interfaces

Compilation failed on humble.
Are there any plans to support Humble in the future?

[TonyWelte]

Humble support is unlikely to come anytime soon (if at all). The message generation was significantly changed in Iron so it would require a significant effort.

Right now I'm focusing on getting the packages released on Rolling and then Jazzy and Kilted.