CMake Cookbook

How to do it

Let us first look at CMakeLists.txt in the root folder:

1. We declare a C++11 project, with a minimum required CMake version:

cmake_minimum_required(VERSION 3.5 FATAL_ERROR)project(recipe-01 LANGUAGES CXX)set(CMAKE_CXX_STANDARD 11)set(CMAKE_CXX_EXTENSIONS OFF)set(CMAKE_CXX_STANDARD_REQUIRED ON)

2. We set the EP_BASE directory property for the current and any underlying directories. This will be discussed shortly:

set_property(DIRECTORY PROPERTY EP_BASE ${CMAKE_BINARY_DIR}/subprojects)

3. We include the ExternalProject.cmake standard module. This module provides the ExternalProject_Add function:

include(ExternalProject)

4. The source code for our "Hello, World" example is added as an external project by invoking the ExternalProject_Add ...