# Notice name prefix of this variable, set by CMake according # to value given with "project()" in the root CMakeLists.txt. include_directories(${gclogger_SOURCE_DIR}/include) add_executable(gclogger main.cpp GcLogger.cpp GcLogger.h SerialPort.cpp SerialPort.h GmcDevice.cpp GmcDevice.h) # I assume you want to use LibProject as a library in MainProject. include_directories(${gclogger_SOURCE_DIR}/libs) link_directories(${gclogger_SOURCE_DIR}/libs)