Combining CMakeLists.txt of Libtorch and CMakeLists.txt of ROS package

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Hello all. I have been struggling with this issue for quite some time, and i request you to please help me. I am fairly new to CMake, so if this is a basic and obvious question, please forgive me.

There is this package called LibTorch, which is a C++ version of PyTorch. As described here, we have to build the code referred to as example-app (in the link) by writing a CMakeLists.txt file. Here are the contents of that CMakeLists.txt file:

cmake_minimum_required(VERSION 3.0 FATAL_ERROR)
project(example-app)

find_package(Torch REQUIRED)
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${TORCH_CXX_FLAGS}")

add_executable(example-app example-app.cpp)
target_link_libraries(example-app "${TORCH_LIBRARIES}")
set_property(TARGET example-app PROPERTY CXX_STANDARD 14)

The example-app.cpp file is a simple C++ file:

#include <torch/torch.h>
#include <iostream>

int main() {
    torch::Tensor tensor = torch::rand({2, 3});
    std::cout << tensor << std::endl;
}

To build this code, consider the folder following hierarchy:

folder/
    example-app.cpp
    CMakeLists.txt

Within the folder, we have to do this:

mkdir build
cd build
cmake -DCMAKE_PREFIX_PATH=/absolute/path/to/libtorch ..
cmake --build . --config Release

where, libtorch is a library folder that contains all the necessary header files etc., and the "/absolute/path/to/libtorch" is the absolute path to where the libtorch library folder is placed. Now, to run the code, we have to go to the build directory and execute the executable generated and we get the output. This works perfectly fine for me. Now, I want to include this library in one of my ROS C++ programs present in the src directory of my package. For my convenience, i have placed the libtorch library folder inside the src folder of my package called "cart_pole", and the ROS C++ program that i want to run is called control_DQN.cpp .

My question is, how do i combine the contents of this CMakeLists.txt and the CMakeLists.txt present in my package directory? Here is my (failed attempt), and I am getting some errors.

cmake_minimum_required(VERSION 3.0)
project(cart_pole)

set(CMAKE_PREFIX_PATH="home/jarvis/catkin_cpp_ws/src/cart_pole/src/libtorch;/opt/ros/melodic")

find_package(catkin REQUIRED COMPONENTS
      roscpp
      rospy
      std_msgs
      std_srvs
      geometry_msgs
      tf
      gazebo_msgs
      message_generation
)
find_package(Torch REQUIRED)
include_directories(
     include
      ${catkin_INCLUDE_DIRS}
      ${Boost_INCLUDE_DIRS}
)
add_executable(control_DQN src/control_DQN.cpp)
target_link_libraries(control_DQN ${catkin_LIBRARIES} ${TORCH_LIBRARIES})
set_property(TARGET control_DQN PROPERTY CXX_STANDARD 14)

Now, when I run the catkin_make command, I get this error:

make[2]: *** No rule to make target '/usr/lib/x86_64-linux-gnu/libconsole_bridge.so.0.4 torch', needed by '/home/jarvis/catkin_cpp_ws/devel/lib/cart_pole/control_DQN'.  Stop.
CMakeFiles/Makefile2:1731: recipe for target 'cart_pole/CMakeFiles/control_DQN.dir/all' failed
make[1]: *** [cart_pole/CMakeFiles/control_DQN.dir/all] Error 2
make[1]: *** Waiting for unfinished jobs....
Makefile:140: recipe for target 'all' failed
make: *** [all] Error 2
Invoking "make -j4 -l4" failed

This error did not come when I built the example-app.cpp code mentioned earlier. So i suppose that ROS catkin_make is missing some paths maybe because i did not specify it in the CMAKE_PREFIX_PATH? The libconsole-bridge-dev is installed correctly and there is no ... (more)