--- Makefile.in.orig	Sat May 10 16:34:04 2014
+++ Makefile.in	Tue Sep 16 13:04:48 2014
@@ -181,4 +181,4 @@ Makefile: Makefile.in
 	    -e 's!@''dotlock@!$(DOTLOCKBASE)!' $@.in > $@
 
 %.o: %.c
-	$(CC) $(CFLAGS) $(DEFS) -c $<
+	$(CC) $(CFLAGS) $(CPPFLAGS) $(DEFS) -c $<
