ament_cmake_symlink_install.cmake breaks CPack

[stewpend0us]

When I do a symlink install and then try to cpack: ament_cmake_symlink_install.cmake fails.

When cpack runs CMAKE_CURRENT_BINARY_DIR is not set. This casuses ament to try to create symlink_install_manifest.txt in the root directory which causes it (and cpack) to fail.

Error message:

CMake Error at /.../.../ament_cmake_symlink_install/ament_cmake_symlink_install.cmake:5 (file):
  file failed to open for writing (Permission denied):

    /symlink_install_manifest.txt

Work around:

manually create /symlink_install_manifest.txt that way ament will find the file and write to it and cpack will not fail.

better yet: ln -s /dev/null /symlink_install_manifest.txt

[stewpend0us]

Welp. Turns out while this does get me an install file the install file doesn't have any content. I gues CMake/CPack aren't capable of following symlinks...

[christophebedard]

Unfortunately, we don't really expect CPack to work with symlink installs.

[stewpend0us]

I was able to get this working. The key was not using colcon --symlink-install and instead setting export CMAKE_INSTALL_MODE=SYMLINK before calling colcon. Then unset CMAKE_INSTALL_MODE after.

This got me both symlinks in my install directory AND working CPack

The only difference I noticed was that the symlinks are relative (CMAKE_INSTALL_MODE) instead of absolute (--symlink-install) but I think there's more going on internal to CMake/CPack with CMAKE_INSTALL_MODE

[christophebedard]

Thanks for the follow-up. I will close this for now, feel free to re-open if there's anything.