Hi everybody, I get this error: CMakeFiles/geometry_based_obstacle_detector.dir/src/geometry_based_obstacle_detector.o: In function `cloudCallback(boost::shared_ptr > const> const&)': /home/skliegl/GETbot/svn/ros/pcl_tools/src/geometry_based_obstacle_detector.cpp:19: undefined reference to `pcl::getPointCloudAsEigen(sensor_msgs::PointCloud2_ > const&, Eigen3::Matrix&)' The mentioned function is: void cloudCallback(const sensor_msgs::PointCloud2ConstPtr& cloud) { Eigen3::MatrixXf points; pcl::getPointCloudAsEigen (*cloud, points); } The corresponding part of the CMakeLists.txt: rosbuild_add_executable( geometry_based_obstacle_detector src/geometry_based_obstacle_detector.cpp) target_link_libraries(geometry_based_obstacle_detector pcl_io) Any ideas? Thank you, Sabrina