catkin build error

[doublestrong]

Hi, I encounter an error when building it. I have class_loader package in /opt/ros/melodic/share/class_loader. The error message is shown as follows. I am trying to build it with the github version of class_loader but am struggling on modifying the CMakelist. Any idea to solve this issue?

chad@chad-Oryx-Pro:~/vnav_ws$ catkin build rviz_textured_quads 
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Profile:                     default
Extending:          [cached] /home/chad/Research/racecar-ws/devel:/home/chad/Research/math_ws/devel:/home/chad/Research/catkin_ws/devel:/opt/ros/melodic
Workspace:                   /home/chad/vnav_ws
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Build Space:        [exists] /home/chad/vnav_ws/build
Devel Space:        [exists] /home/chad/vnav_ws/devel
Install Space:      [unused] /home/chad/vnav_ws/install
Log Space:          [exists] /home/chad/vnav_ws/logs
Source Space:       [exists] /home/chad/vnav_ws/src
DESTDIR:            [unused] None
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Devel Space Layout:          linked
Install Space Layout:        None
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Additional CMake Args:       -DCMAKE_BUILD_TYPE=Debug
Additional Make Args:        None
Additional catkin Make Args: None
Internal Make Job Server:    True
Cache Job Environments:      False
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Whitelisted Packages:        None
Blacklisted Packages:        None
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WARNING: Your current environment's CMAKE_PREFIX_PATH is different from the cached CMAKE_PREFIX_PATH used the last time this workspace was built.

If you want to use a different CMAKE_PREFIX_PATH you should call `catkin clean` to remove all references to the previous CMAKE_PREFIX_PATH.

Cached CMAKE_PREFIX_PATH:
	/home/chad/Research/racecar-ws/devel:/home/chad/Research/math_ws/devel:/home/chad/Research/catkin_ws/devel:/opt/ros/melodic
Current CMAKE_PREFIX_PATH:
	/opt/ros/melodic
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[build] Found '57' packages in 0.0 seconds.                                                                                                                                   
[build] Package table is up to date.                                                                                                                                          
Starting  >>> class_loader                                                                                                                                                    
Finished  <<< class_loader                       [ 0.2 seconds ]                                                                                                              
Starting  >>> rviz_textured_quads                                                                                                                                             
______________________________________________________________________________________________________________________________________________________________________________
Errors     << rviz_textured_quads:cmake /home/chad/vnav_ws/logs/rviz_textured_quads/build.cmake.018.log                                                                       
CMake Warning (dev) at /usr/src/googletest/CMakeLists.txt:3 (project):
  Policy CMP0048 is not set: project() command manages VERSION variables.
  Run "cmake --help-policy CMP0048" for policy details.  Use the cmake_policy
  command to set the policy and suppress this warning.

  The following variable(s) would be set to empty:

    PROJECT_VERSION
    PROJECT_VERSION_MAJOR
    PROJECT_VERSION_MINOR
    PROJECT_VERSION_PATCH
This warning is for project developers.  Use -Wno-dev to suppress it.

CMake Warning (dev) at /usr/src/googletest/googlemock/CMakeLists.txt:40 (project):
  Policy CMP0048 is not set: project() command manages VERSION variables.
  Run "cmake --help-policy CMP0048" for policy details.  Use the cmake_policy
  command to set the policy and suppress this warning.

  The following variable(s) would be set to empty:

    PROJECT_VERSION
    PROJECT_VERSION_MAJOR
    PROJECT_VERSION_MINOR
    PROJECT_VERSION_PATCH
This warning is for project developers.  Use -Wno-dev to suppress it.

CMake Warning (dev) at /usr/src/googletest/googletest/CMakeLists.txt:47 (project):
  Policy CMP0048 is not set: project() command manages VERSION variables.
  Run "cmake --help-policy CMP0048" for policy details.  Use the cmake_policy
  command to set the policy and suppress this warning.

  The following variable(s) would be set to empty:

    PROJECT_VERSION
    PROJECT_VERSION_MAJOR
    PROJECT_VERSION_MINOR
    PROJECT_VERSION_PATCH
This warning is for project developers.  Use -Wno-dev to suppress it.

CMake Error at /opt/ros/melodic/share/class_loader/cmake/class_loaderConfig.cmake:173 (message):
  Project 'rviz_textured_quads' tried to find library 'dl'.  The library is
  neither a target nor built/installed properly.  Did you compile project
  'class_loader'? Did you find_package() it before the subdirectory
  containing its code is included?
Call Stack (most recent call first):
  /opt/ros/melodic/share/pluginlib/cmake/pluginlibConfig.cmake:197 (find_package)
  /opt/ros/melodic/share/catkin/cmake/catkinConfig.cmake:76 (find_package)
  CMakeLists.txt:6 (find_package)


cd /home/chad/vnav_ws/build/rviz_textured_quads; catkin build --get-env rviz_textured_quads | catkin env -si  /usr/bin/cmake /home/chad/vnav_ws/src/rviz_textured_quads --no-warn-unused-cli -DCATKIN_DEVEL_PREFIX=/home/chad/vnav_ws/devel/.private/rviz_textured_quads -DCMAKE_INSTALL_PREFIX=/home/chad/vnav_ws/install -DCMAKE_BUILD_TYPE=Debug; cd -
..............................................................................................................................................................................
Failed     << rviz_textured_quads:cmake          [ Exited with code 1 ]                                                                                                       
Failed    <<< rviz_textured_quads                [ 0.6 seconds ]                                                                                                              
[build] Summary: 1 of 2 packages succeeded.                                                                                                                                   
[build]   Ignored:   55 packages were skipped or are blacklisted.                                                                                                             
[build]   Warnings:  None.                                                                                                                                                    
[build]   Abandoned: None.                                                                                                                                                    
[build]   Failed:    1 packages failed.                                                                                                                                       
[build] Runtime: 0.9 seconds total.

[lucasw]

I notice your workspace extension has a lot in it:

Extending:          [cached] /home/chad/Research/racecar-ws/devel:/home/chad/Research/math_ws/devel:/home/chad/Research/catkin_ws/devel:/opt/ros/melodic

Also this is a clue that your workspaces are possibly fouled up:

WARNING: Your current environment's CMAKE_PREFIX_PATH is different from the cached CMAKE_PREFIX_PATH used the last time this workspace was built.

You may want to try compiling in a simpler clean setup that only extends /opt/ros/melodic and add more workspaces from there.

The action files may provide some clues also, take a look at what this file https://github.com/lucasw/rviz_textured_quads/blob/image_topic/.github/workflows/ubuntu_18_04.yml does to build the package.

[lucasw]

Another thing is that maybe class_loader doesn't really belong in the dependencies at all (I could have left it in there when I forked this package originally), you could try removing it from package.xml and CMakeLists.txt.