Build sample with CMake and C++

Godot Version

3.5.1

Question

Unable to build the project using SMake.

  1. Created an empty project using the Godot application
  2. Installed Python 3.4.0
  3. Downloaded GitHub - godotengine/godot-cpp: C++ bindings for the Godot script API and unpacked to <my_lib_name>/godot-cpp-master
  4. Downloaded GitHub - godotengine/godot-headers: Headers for the Godot API supplied by the GDNative module. and unpacked to <my_lib_name>/godot-cpp-master/godot_headers
  5. Created <my_lib_name>/CMakeLists.txt with the following code
# CMake version and project name 
cmake_minimum_required(VERSION 3.20)
project(GodotSample)

# Exoprt compile commands for clangd 
set(CMAKE_EXPORT_COMPILE_COMMANDS ON)

# CXX Settings
set(CMAKE_CXX_STANDARD 20)
set(CMAKE_CXX_STANDARD_REQUIRED ON)
set(CMAKE_CXX_EXTENSIONS OFF)

# Output directroies
include(GNUInstallDirs)
set(CMAKE_ARCHIVE_OUTPUT_DIRECTORY
  ${CMAKE_CURRENT_SOURCE_DIR}/${CMAKE_INSTALL_LIBDIR})
set(CMAKE_LIBRARY_OUTPUT_DIRECTORY
  ${CMAKE_CURRENT_SOURCE_DIR}/${CMAKE_INSTALL_LIBDIR})
set(CMAKE_RUNTIME_OUTPUT_DIRECTORY
  ${CMAKE_CURRENT_SOURCE_DIR}/${CMAKE_INSTALL_BINDIR})

# Sources subdirectories
add_subdirectory(godot-cpp-master)
add_subdirectory(Sample)
  1. Created <my_lib_name>/<my_lib_name>/CMakeLists.txt with the following code
# Headers
set(headers
  inc/controller.hpp)

# Sources
set(sources
  ${headers}
  src/godot_lib.cpp
  src/controller.cpp)

# Output .dll library
add_library(sample SHARED
  ${sources})

# Used modules
target_link_libraries(sample
  PRIVATE
    godot-cpp)

# Include directories  
target_include_directories(sample
  PUBLIC
    $<INSTALL_INTERFACE:include>
    $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/include>
  PRIVATE
    ${CMAKE_CURRENT_SOURCE_DIR}/src)  

Project structure:

Sample/
build/
godot-cpp-master/

Sample/
inc/
controller.hpp
src/
controller.cpp
godot_lib.cpp
CMakeLists.txt

CMakeLists.txt

default_env.tres
icon.png
icon.png.import
project.godot

When trying to generate cmake I get the following error:

What could be the problem and how to solve it?