-- The CXX compiler identification is unknown   
        -- The C compiler identification is GNU 5.4.0   
        CMake Error at CMakeLists.txt:127 (project):   
        The CMAKE_CXX_COMPILER:   
        arm-linux-gnueabihf-g++   
        is not a full path and was not found in the PATH.   
        Tell CMake where to find the compiler by setting either the environment   
        variable "CXX" or the CMake cache entry CMAKE_CXX_COMPILER to the full path   
        to the compiler, or to the compiler name if it is in the PATH.