diff --git a/src/util-proto-name.c b/src/util-proto-name.c
index 0b958884ca..2392682d7b 100644
--- a/src/util-proto-name.c
+++ b/src/util-proto-name.c
@@ -27,6 +27,9 @@
 #include "suricata-common.h"
 #include "util-proto-name.h"
 
+/** Lookup array to hold the information related to known protocol
+ *  in /etc/protocols */
+char *known_proto[256];
 static int init_once = 0;
 
 /**
diff --git a/src/util-proto-name.h b/src/util-proto-name.h
index e349a6db2e..7cf69df928 100644
--- a/src/util-proto-name.h
+++ b/src/util-proto-name.h
@@ -32,7 +32,7 @@
 
 /** Lookup array to hold the information related to known protocol
  *  in /etc/protocols */
-char *known_proto[256];
+extern char *known_proto[256];
 
 uint8_t SCProtoNameValid(uint16_t);
 void SCProtoNameInit(void);