diff --git a/sys/netgraph/ng_device.c b/sys/netgraph/ng_device.c
index 8873900ffcb6..d5af1323ba20 100644
--- a/sys/netgraph/ng_device.c
+++ b/sys/netgraph/ng_device.c
@@ -31,9 +31,9 @@
  */
 
 #if 0
-#define DBG printf("ng_device: %s\n", __func__ )
+#define	DBG do { printf("ng_device: %s\n", __func__ ); } while (0)
 #else
-#define DBG
+#define	DBG do {} while (0)
 #endif
 
 #include <sys/param.h>
diff --git a/sys/netgraph/ng_pppoe.c b/sys/netgraph/ng_pppoe.c
index 957c2f055ca1..511ca2d20449 100644
--- a/sys/netgraph/ng_pppoe.c
+++ b/sys/netgraph/ng_pppoe.c
@@ -40,9 +40,9 @@
  * $Whistle: ng_pppoe.c,v 1.10 1999/11/01 09:24:52 julian Exp $
  */
 #if 0
-#define DBG printf("pppoe: %s\n", __func__ )
+#define	DBG do { printf("ng_device: %s\n", __func__ ); } while (0)
 #else
-#define DBG
+#define	DBG do {} while (0)
 #endif
 
 #include <sys/param.h>