ROS2 Foxy composable node: Failed to load component due to undefined symbol

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Dear all,

I am developing a composable ROS 2 lifecycle node. The node uses another external library in order to execute EtherCAT Master functionalities. I have followed the composition tutorial page:

1. I created a container process in terminal.
2. Then, I tried to load the node.

The error I am getting is the following:

Failed to load component: Failed to load library: could not load library loadlibrary error: /home/mobile/dev_ws/install/ether_ros2/lib/libether_ros2_component.so: undefined symbol: _ztvn10ether_ros220ethercatcommunicatore, at /tmp/binarydeb/ros-foxy-rcutils-1.1.3/src/shared_library.c:84

CMakeLists.txt

cmake_minimum_required(VERSION  3.5)
project(ether_ros2)

# Default to C++17
if(NOT CMAKE_CXX_STANDARD)
  set(CMAKE_CXX_STANDARD 17)
endif()

if(CMAKE_COMPILER_IS_GNUCXX OR CMAKE_CXX_COMPILER_ID MATCHES "Clang")
  add_compile_options(-Wall -Wextra -Wpedantic)
endif()

# find dependencies
find_package(ament_cmake REQUIRED)

#find YAML dependency
find_package(yaml_cpp_vendor REQUIRED)

find_package(rclcpp REQUIRED)
find_package(rclcpp_components REQUIRED)
find_package(rclcpp_lifecycle REQUIRED)
find_package(lifecycle_msgs REQUIRED)
find_package(builtin_interfaces REQUIRED)
find_package(rcutils REQUIRED)
find_package(std_msgs REQUIRED)
find_package(rosidl_default_generators REQUIRED)

 # create ament index resource which references the libraries in the binary dir
 set(node_plugins "")
 rosidl_generate_interfaces(${PROJECT_NAME}
      "msg/PdoIn.msg"
      "msg/PdoInXmc.msg"
      "msg/PdoOut.msg"
      "msg/PdoRaw.msg"
      "msg/ModifyPdoVariables.msg"
       DEPENDENCIES builtin_interfaces std_msgs
 )

set(etherlab_include /opt/etherlab/include)
set(etherlab_lib /opt/etherlab/lib/libethercat.so)

set(SOURCES
      src/ether_ros2_component.cpp
      src/utilities.cpp
      src/ethercat_communicator.cpp
      src/ethercat_network.cpp
      src/ethercat_slave.cpp
      src/pdo_in_publisher.cpp
      src/pdo_out_publisher.cpp
      src/pdo_out_listener.cpp
      src/pdo_out_publisher_timer.cpp)

include_directories(include
                    ${etherlab_include})

add_library(${PROJECT_NAME}_component SHARED
  ${SOURCES})

target_compile_definitions(${PROJECT_NAME}_component
      PRIVATE "COMPOSITION_BUILDING_DLL")
target_link_libraries(${PROJECT_NAME}_component
      ${etherlab_lib})

ament_target_dependencies(${PROJECT_NAME}_component
  "rclcpp"
  "rclcpp_components"
  "rclcpp_lifecycle"
  "lifecycle_msgs"
  "rosidl_default_generators"
  "std_msgs"
  "builtin_interfaces"
  "yaml_cpp_vendor"
  "rcutils")

rosidl_target_interfaces(${PROJECT_NAME}_component
          ${PROJECT_NAME} "rosidl_typesupport_cpp")

rclcpp_components_register_nodes(${PROJECT_NAME}_component "ether_ros2::EthercatCommunicator")
set(node_plugins "${node_plugins}ether_ros2::EthercatCommunicator;$<TARGET_FILE:ether_ros2_component>\n")

install(TARGETS
    ${PROJECT_NAME}_component
    ARCHIVE DESTINATION lib
    LIBRARY DESTINATION lib
    RUNTIME DESTINATION bin)

ament_package()

Note that the package has been built successfully. How can I resolve this error ?

Thank you for your help.

Best Regards,

Aris.