How to do it

We will construct the CMakeLists.txt step by step and show how to require a certain standard (in this case C++14):

1. We state the minimum required CMake version, project name, and language:

cmake_minimum_required(VERSION 3.5 FATAL_ERROR)

project(recipe-09 LANGUAGES CXX)

2. We request all library symbols to be exported on Windows:

set(CMAKE_WINDOWS_EXPORT_ALL_SYMBOLS ON)

3. We need to add a target for the library. This will compile the sources into a shared library:

add_library(animals
  SHARED
    Animal.cpp
    Animal.hpp
    Cat.cpp
    Cat.hpp
    Dog.cpp
    Dog.hpp
    Factory.hpp
  )

4.  We now set the CXX_STANDARD, CXX_EXTENSIONS, and CXX_STANDARD_REQUIRED properties for the target. We also set the POSITION_INDEPENDENT_CODE property, to avoid issues when building the DSO with some compilers:

set_target_properties(animals
  PROPERTIES
    CXX_STANDARD 14
    CXX_EXTENSIONS OFF
    CXX_STANDARD_REQUIRED ON
    POSITION_INDEPENDENT_CODE 1
  )

5. Then, we add a new target for the animal-farm executable and set its properties:

add_executable(animal-farm animal-farm.cpp)

set_target_properties(animal-farm
  PROPERTIES
    CXX_STANDARD 14
    CXX_EXTENSIONS OFF
    CXX_STANDARD_REQUIRED ON
  )

6.  Finally, we link the executable to the library:

target_link_libraries(animal-farm animals)

7. Let us also check what our example cat and dog have to say:

$ mkdir -p build
$ cd build
$ cmake ..
$ cmake --build .
$ ./animal-farm

I'm Simon the cat!
I'm Marlowe the dog!