diff --git a/sys/unix/Makefile.utl b/sys/unix/Makefile.utl
index 885e79ce9..c30bfcf20 100644
--- a/sys/unix/Makefile.utl
+++ b/sys/unix/Makefile.utl
@@ -174,7 +174,7 @@ YACCDIST =
 
 #	dependencies for makedefs
 #
-makedefs:	$(MAKEOBJS)
+makedefs:	$(MAKEOBJS) mdgrep.h
 	$(CC) $(LFLAGS) -o makedefs $(MAKEOBJS)
 
 makedefs.o: makedefs.c $(CONFIG_H) ../include/permonst.h \