execute_process(COMMAND git rev-parse HEAD OUTPUT_VARIABLE VERSION_PATCH) # remove leading and trailing spaces string(STRIP "${VERSION_PATCH}" VERSION_PATCH) message("Checking time stamp ...") if(EXISTS ${TIME_STAMP_FILE}) file (STRINGS ${TIME_STAMP_FILE} VERSION_IN_FILE) if(NOT "${VERSION_IN_FILE}" STREQUAL "${VERSION_PATCH}") file (REMOVE "${TIME_STAMP_FILE}") endif() endif()