eigen3 cmake error within a docker container - cmake

Question

I am trying to build a ROS2 package, and I get this error
CMake Error at /opt/ros/foxy/share/ament_cmake_target_dependencies/cmake/ament_target_dependencies.cmake:66 (message):
ament_target_dependencies() the passed package name 'Eigen3::Eigen' was not
found before
Call Stack (most recent call first):
CMakeLists.txt:83 (ament_target_dependencies)
I am trying to solve it using this, however i cannot identify which is my source folder for eigen3 installation.
What changes should I should make to my CMakelist?
libeigen3-dev is already the newest version (3.3.7-2).
and also
ros-foxy-eigen3-cmake-module is already the newest version(0.1.1-1focal.20210423.000604).
CMakelist:
cmake_minimum_required(VERSION 3.5)
project(avoidance)
if(CMAKE_COMPILER_IS_GNUCXX OR CMAKE_CXX_COMPILER_ID MATCHES "Clang")
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall -Wextra -Wpedantic")
endif()
find_package(ament_cmake REQUIRED)
find_package(builtin_interfaces REQUIRED)
find_package(perception_pcl REQUIRED)
find_package(rclcpp REQUIRED)
find_package(tf2 REQUIRED)
get_default_rmw_implementation(rmw_implementation)
find_package("${rmw_implementation}" REQUIRED)
find_package(geometry_msgs REQUIRED)
find_package(px4_msgs REQUIRED)
find_package(sensor_msgs REQUIRED)
find_package(std_msgs REQUIRED)
find_package(PythonInterp REQUIRED)
find_package(eigen3_cmake_module REQUIRED)
find_package(Eigen3 REQUIRED NO_MODULE)
find_package(Boost REQUIRED COMPONENTS system)
find_package(PCL REQUIRED)
if(DISABLE_SIMULATION)
message(STATUS "Building avoidance without Gazebo Simulation")
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -DDISABLE_SIMULATION")
else()
message(STATUS "Building avoidance with Gazebo Simulation")
find_package(yaml-cpp REQUIRED)
endif(DISABLE_SIMULATION)
#################
# Setup targets #
#################
## CMake Setup
# Build in Release mode if nothing is specified
if(NOT CMAKE_BUILD_TYPE)
set(CMAKE_BUILD_TYPE Release)
endif(NOT CMAKE_BUILD_TYPE)
## Specify additional locations of header files
include_directories(
include
${rclcpp_INCLUDE_DIRS}
${PCL_INCLUDE_DIRS}
${YAML_CPP_INCLUDE_DIR}
)
## Declare a C++ library
set(AVOIDANCE_CPP_FILES
"src/common.cpp"
"src/histogram.cpp"
"src/transform_buffer.cpp"
"src/avoidance_node.cpp"
)
if(NOT DISABLE_SIMULATION)
set(AVOIDANCE_CPP_FILES "${AVOIDANCE_CPP_FILES}" "src/rviz_world_loader.cpp")
endif()
# Add avoidance lib
add_library(avoidance SHARED "${AVOIDANCE_CPP_FILES}")
ament_target_dependencies(avoidance Eigen3 px4_msgs ${${PROJECT_NAME}_EXPORTED_TARGETS})
target_include_directories(avoidance PUBLIC
$<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/include/${PROJECT_NAME}>
$<INSTALL_INTERFACE:include/${PROJECT_NAME}>
${Eigen3_INCLUDE_DIRS}
)
## Specify libraries to link a library or executable target against
target_link_libraries(
avoidance
Eigen3::Eigen
${YAML_CPP_LIBRARIES}
)
# Add node dependencies
ament_target_dependencies(avoidance px4_msgs rclcpp Eigen3::Eigen)
# Export information to downstream packages
ament_export_dependencies(ament_cmake rclcpp rosidl_default_runtime eigen3_cmake_module Eigen3 px4_msgs geometry_msgs sensor_msgs std_msgs)
ament_export_interfaces(export_avoidance HAS_LIBRARY_TARGET)
ament_export_include_directories(include)
ament_export_libraries(avoidance)
#############
## Install ##
#############
# Install header files
install(DIRECTORY include/${PROJECT_NAME}/
DESTINATION include/${PROJECT_NAME}
FILES_MATCHING PATTERN "*.h"
PATTERN ".svn" EXCLUDE
)
# Install artifacts
install(TARGETS avoidance
EXPORT export_avoidance
ARCHIVE DESTINATION lib
LIBRARY DESTINATION lib
RUNTIME DESTINATION bin
INCLUDES DESTINATION include
)
# Install launch files
install(DIRECTORY
launch
DESTINATION share/${PROJECT_NAME}
)
#############
## Testing ##
#############
# if(CATKIN_ENABLE_TESTING)
# # Add gtest based cpp test target and link libraries
# catkin_add_gtest(${PROJECT_NAME}-test test/main.cpp
# test/test_common.cpp
# test/test_usm.cpp
# test/test_transform_buffer.cpp
# )
#
# if(TARGET ${PROJECT_NAME}-test)
# target_link_libraries(${PROJECT_NAME}-test ${PROJECT_NAME}
# ${catkin_LIBRARIES}
# ${YAML_CPP_LIBRARIES})
# endif()
#
#
# if (${CMAKE_BUILD_TYPE} STREQUAL "Coverage")
# SET(CMAKE_CXX_FLAGS "-g -O0 -fprofile-arcs -ftest-coverage --coverage")
# SET(CMAKE_C_FLAGS "-g -O0 -fprofile-arcs -ftest-coverage --coverage")
# SET(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} --coverage")
#
# add_custom_target(${PROJECT_NAME}-test_coverage
# COMMAND lcov --zerocounters --directory ${PROJECT_BINARY_DIR}
# COMMAND lcov --capture --initial --no-external --directory ${PROJECT_BINARY_DIR} --base-directory ${${PROJECT_NAME}_SOURCE_DIR} --output-file base_coverage.info --rc lcov_branch_coverage=1
# COMMAND ${PROJECT_NAME}-test
# COMMAND lcov --capture --no-external --directory ${PROJECT_BINARY_DIR} --base-directory ${${PROJECT_NAME}_SOURCE_DIR} --output-file test_coverage.info --rc lcov_branch_coverage=1
# COMMAND lcov -a base_coverage.info -a test_coverage.info -o coverage.info --rc lcov_branch_coverage=1
# COMMAND lcov --rc lcov_branch_coverage=1 --summary coverage.info
# WORKING_DIRECTORY .
# DEPENDS ${PROJECT_NAME}-test
# )
# add_custom_target(${PROJECT_NAME}-test_coverage_html
# COMMAND genhtml coverage.info --output-directory out --branch-coverage
# COMMAND x-www-browser out/index.html
# WORKING_DIRECTORY .
# DEPENDS ${PROJECT_NAME}-test_coverage
# )
# endif()
# endif()
ament_package()

Answer 1

Taking a look at nav2_smac_planner/CMakeLists.txt
I found that you actually use Eigen3 inside the ament_target_dependencies instead of eigen3_cmake_module.
There they also export it in ament_export_dependencies.
So... for including the header, you should use Eigen3, but dependency-wise, eigen3_cmake_modules should be used.