--- a/Makefile.defs.in
+++ b/Makefile.defs.in
@@ -24,6 +24,7 @@ LDFLAGS		+= @LIBS@
 
 CPPFLAGS	+= @CPPFLAGS@
 
+CFLAGS		:=
 CFLAGS		+= @CFLAGS@ @DEFS@
 CFLAGS		+= -DDEFAULT_INCLUDE_PATH="\"$(confdir)\""
 CFLAGS		+= -include config.h
