Unable to bundle DeepState through CMake add_subdirectory

[laurynas-biveinis]

If I try to bundle DeepState as a git submodule in a project and build it through add_subdirectory(3rd_party/deepstate) in the main CMakeLists.txt, the configure step fails with

...
CMake Deprecation Warning at 3rd_party/deepstate/CMakeLists.txt:16 (cmake_minimum_required):
  Compatibility with CMake < 2.8.12 will be removed from a future version of
  CMake.

  Update the VERSION argument <min> value or use a ...<max> suffix to tell
  CMake that the project does not need compatibility with older versions.


CMake Error: File /Users/laurynas/unodb/deepstate-cmake-add-subdirectory/bin/setup.py.in does not exist.
CMake Error at 3rd_party/deepstate/CMakeLists.txt:285 (configure_file):
  configure_file Problem configuring file

This seems to be caused by

set(SETUP_PY_IN "${CMAKE_SOURCE_DIR}/bin/setup.py.in")

using CMAKE_SOURCE_DIR instead of CMAKE_CURRENT_SOURCE_DIR perhaps?