project(External) enable_language(CXX) file(WRITE "${CMAKE_CURRENT_BINARY_DIR}/generated.cxx" "") add_executable(generated_exe empty.c) target_sources(generated_exe PRIVATE "${CMAKE_CURRENT_BINARY_DIR}/generated.cxx") source_group("Generated Source Files" FILES "${CMAKE_CURRENT_BINARY_DIR}/generated.cxx") set_property(SOURCE "${CMAKE_CURRENT_BINARY_DIR}/generated.cxx" PROPERTY GENERATED ON) set_property(SOURCE empty.c PROPERTY COMPILE_DEFINITIONS EMPTY_C=1 SRC_DUMMY) set_property(SOURCE empty.c PROPERTY INCLUDE_DIRECTORIES "${CMAKE_CURRENT_BINARY_DIR}") target_include_directories(generated_exe SYSTEM PRIVATE "${CMAKE_CURRENT_SOURCE_DIR}") target_compile_definitions(generated_exe PRIVATE GENERATED_EXE=1 -DTGT_DUMMY)