+# Sanity check user supplied values
+$(foreach MANDATORY_VAR, $(LUFA_BUILD_MANDATORY_VARS), $(call ERROR_IF_UNSET, $(MANDATORY_VAR)))
+$(call ERROR_IF_EMPTY, SRC)
+$(call ERROR_IF_EMPTY, CPPCHECK_MSG_TEMPLATE)
+$(call ERROR_IF_EMPTY, CPPCHECK_ENABLE)
+$(call ERROR_IF_NONBOOL, CPPCHECK_FAIL_ON_WARNING)
+$(call ERROR_IF_NONBOOL, CPPCHECK_QUIET)
+