Invoking "make -j2 -l2" failed

edit

Hi, i followed exactly the instructions here http://erlerobotics.com/docs/Simulati... , everything went find except the very last command :::

Then compile everything together:

cd ~/simulation/ros_catkin_ws
source devel/setup.bash catkin_make

Error in the terminal :

[ 98%] Building CXX object ardupilot_sitl_gazebo_plugin/ardupilot_sitl_gazebo_plugin/CMakeFiles/ardupilot_sitl_gazebo_plugin.dir/src/SocketAPM.cpp.o
Linking CXX shared library /home/omaralhebsi/simulation/ros_catkin_ws/devel/lib/libardupilot_sitl_gazebo_plugin.so
[ 98%] Built target ardupilot_sitl_gazebo_plugin
make: * [all] Error 2 Invoking "make -j2 -l2" failed

What do i have to do ?? , plz help its only one step and then i can start working on Gazebo . I guess the problem is with catkin_make

i ran the code again and this is what i received :

[100%] Built target sitl_test_node /home/simulation/ros_catkin_ws/src/gazebo_cpp_examples/erle-copter_pattern_follower/src/image_subscriber.cpp:5:25:
fatal error: aruco/aruco.h: No such file or directory #include <aruco aruco.h=""> ^ compilation terminated. 
make[2]: * [gazebo_cpp_examples/erle-copter_pattern_follower/CMakeFiles/ros_erle_pattern_follower.dir/src/image_subscriber.cpp.o] Error 1 make[1]: [gazebo_cpp_examples/erle-copter_pattern_follower/CMakeFiles/ros_erle_pattern_follower.dir/all] Error 2 make: ** [all] Error 2 Invoking "make -j2 -l2" failed