diff --git a/lib/script/script.h b/lib/script/script.h
index 1c1b90d0a..6fcd6c0eb 100644
--- a/lib/script/script.h
+++ b/lib/script/script.h
@@ -66,7 +66,7 @@ extern void scriptSetTypeEquiv(TYPE_EQUIV *psTypeTab);
  *
  * \return Number of calls on the return address stack
  */
-inline Sint8 retStackCallDepth(void);
+extern Sint8 retStackCallDepth(void);
 
 
 /***********************************************************************************