Jax

@jlaine What kind of unit test should I add for this pull request? Sorry, I'm not familiar with the progress of pull request.

填写键值对 key: CMAKE_CXX_COMPILER value: clang++ 如果是用的QtCreator来编译，也可以在QtCreator的偏好设置 Build&Run，Kits中指定C和C++的编译器