--- a/Make.spec	Wed Nov 09 00:32:53 2016 +0100
+++ b/Make.spec	Wed Nov 09 00:35:31 2016 +0100
@@ -106,6 +106,7 @@
 	UndefinedObject \
 	UserMessage \
 	Visitor \
+	VoidObject \
 	AbstractTime \
 	ApplicationDefinition \
 	ArithmeticValue \
@@ -496,6 +497,7 @@
     $(OUTDIR_SLASH)UndefinedObject.$(O) \
     $(OUTDIR_SLASH)UserMessage.$(O) \
     $(OUTDIR_SLASH)Visitor.$(O) \
+    $(OUTDIR_SLASH)VoidObject.$(O) \
     $(OUTDIR_SLASH)AbstractTime.$(O) \
     $(OUTDIR_SLASH)ApplicationDefinition.$(O) \
     $(OUTDIR_SLASH)ArithmeticValue.$(O) \