/share directory and tutorial.repos file are not created after ros_cross_compile

[jg-spitfire]

Hi, I am using the tool in a VM running Ubuntu 18.04.04, after the installation (I install the latest Docker engine), I follow the tutorial but after the ros_cross_compile command I realize that:

1.- tutorial.repos is not created in my workspace 2.- the path install_aarch64/share is unreachable because the share directory is not created, I realize this when I copy the directory install_aarch64 to my target device and run

rosdep install --from-paths install_aarch64/share --ignore-src --rosdistro foxy -y

I got an error that says the path install_aarch64/share is not found

What could be the problem?

[emersonknapp]

1. tutorial.repos is left over from an old version of the tutorial, this is not something that the build should create. I have removed it from the list of files in the README.
2. Thanks for reporting this! The install/share directory will only be there if the build was created with --merge-install. Otherwise, each individual built package will have its own install/PACKAGE/share directory. For this portion of the tutorial, I would recommend adding merge install to the defaults.yaml. It's easier to use merge-installed colcon outputs across machines, so this is probably best practice for a deployable artifact anyways.

I am also noticing that a bug was introduced in the 0.9 version so that a defaults.yaml in the workspace directory will not be respected unless explicitly specified.

I have updatd the README in https://github.com/ros-tooling/cross_compile/commit/921884ef5eca9017df390d9e664ce4e1d83e5316 to have the correct commands necessary for the tutorial to work as expected at the moment, and will try to put in a fix for the defaults.yaml thing shortly.

[jg-spitfire]

@emersonknapp Hi, did you test this with a target platform?, now the share directory is created but when I run in my target:

from sudo apt update && sudo apt install -y python3-rosdep

from sudo rosdep init rosdep update

from your tutorial: rosdep install --from-paths install_aarch64/share --ignore-src --rosdistro foxy -y

I got an error:

E: Unable to locate package ros-foxy-example-interfaces ERROR: the following rosdeps failed to install apt: command [sudo -H apt-get install -y ros-foxy-example-interfaces] failed

My target is a custom Linux distribution from Xilinx built from Yocto, its name is Petalinux, and I installed Ubuntu 20.04 LTS arm64 over that distro

[emersonknapp]

Assuming you have APT on this platform and have ROS dependencies you need to install that way, you still need to set up the ROS 2 APT sources as you would for any system, as described at https://docs.ros.org/en/foxy/Installation/Ubuntu-Install-Debians.html#setup-sources. I have added some language in https://github.com/ros-tooling/cross_compile/commit/ccc64975355d70c8e24dbd3815d7dabb3fd29b28 calling this out.

I am assuming that's the problem you're experiencing here.

Thanks for reporting and following up on these issues - it will improve the experience for others

[jg-spitfire]

I already try that, I followed this steps: add the repo, even I installed the development tools, and I get the error I mentioned before

[emersonknapp]

You shouldn't need the development tools - that's for building, which you have already done.

I wonder if maybe the sources setup didn't work correctly for your custom distro.

• Are you able to sudo apt-cache search ros-foxy - does this show any packages at all?
• What are the contents of /etc/apt/sources.list.d/ros2.list?
• Are there any errors when you apt-get update?

[jg-spitfire]

hi @emersonknapp I could solve the error:

E: Unable to locate package ros-foxy-example-interfaces ERROR: the following rosdeps failed to install apt: command [sudo -H apt-get install -y ros-foxy-example-interfaces] failed

it was my fault, I was using a 32 bits ubuntu distro in my embedded linux instead a 64 bits, once I run rosdep install --from-paths install_aarch64/share --ignore-src --rosdistro foxy -y a message says that all rosdep dependencies were installed, then I write this commands:

source install_aarch64/setup.bash ros2 run demo_nodes_cpp talker

but now I get: -bash: ros2: command not found

I will answer your questions: 1.- Are you able to sudo apt-cache search ros-foxy - does this show any packages at all?

2.- What are the contents of /etc/apt/sources.list.d/ros2.list?

3.- Are there any errors when you apt-get update? no, I can make updates, upgrades and install packages without issues

[jg-spitfire]

"Assuming you have APT on this platform and have ROS dependencies you need to install that way, you still need to set up the ROS 2 APT sources as you would for any system"

What dependencies are you talking about?

[jg-spitfire]

I used the sudo apt install ros-foxy-ros-base and then works!, but that step is not in your tutorial

[jg-spitfire]

@emersonknapp when testing the demo in the target board you must add the sources for the listener too:

source install_aarch64/setup.bash ros2 run demo_nodes_cpp talker

#and in a different shell, add sources too source install_aarch64/setup.bash ros2 run demo_nodes_cpp listener