set(CMAKE_DISABLE_SOURCE_CHANGES ON)
add_custom_command(OUTPUT a BYPRODUCTS "a#")
add_custom_command(OUTPUT b BYPRODUCTS "a<")
add_custom_command(OUTPUT c BYPRODUCTS "a>")
add_custom_command(OUTPUT d BYPRODUCTS "$<CONFIG>/#")
add_custom_command(OUTPUT e BYPRODUCTS ${CMAKE_CURRENT_SOURCE_DIR}/f)