diff --git a/include/iwinfo.h b/include/iwinfo.h
index 90e5906..71fadab 100644
--- a/include/iwinfo.h
+++ b/include/iwinfo.h
@@ -84,9 +84,11 @@ enum iwinfo_opmode {
 	IWINFO_OPMODE_MESHPOINT  = 7,
 	IWINFO_OPMODE_P2P_CLIENT = 8,
 	IWINFO_OPMODE_P2P_GO     = 9,
+
+	IWINFO_OPMODE_COUNT      = 10,
 };
 
-extern const char * const IWINFO_OPMODE_NAMES[];
+extern const char * const IWINFO_OPMODE_NAMES[IWINFO_OPMODE_COUNT];
 
 
 enum iwinfo_htmode {
diff --git a/iwinfo_lib.c b/iwinfo_lib.c
index 93d4b25..353ecb8 100644
--- a/iwinfo_lib.c
+++ b/iwinfo_lib.c
@@ -49,7 +49,7 @@ const char * const IWINFO_AUTH_NAMES[IWINFO_AUTH_COUNT] = {
 	"SHARED",
 };
 
-const char * const IWINFO_OPMODE_NAMES[] = {
+const char * const IWINFO_OPMODE_NAMES[IWINFO_OPMODE_COUNT] = {
 	"Unknown",
 	"Master",
 	"Ad-Hoc",