include(ExternalProject)

ExternalProject_Add(EnvModification
  SOURCE_DIR "${CMAKE_CURRENT_SOURCE_DIR}/EnvVars"
  DOWNLOAD_COMMAND ""
  UPDATE_COMMAND ""
  PATCH_COMMAND ""
  LIST_SEPARATOR :
  CONFIGURE_ENVIRONMENT_MODIFICATION
    HI
    INVALID=SETTING
    INVALID=OP1:operation:10)