diff --git a/src/vim9.h b/src/vim9.h
index cffa71b..88c0469 100644
--- a/src/vim9.h
+++ b/src/vim9.h
@@ -322,7 +322,8 @@
 
 // arguments to ISN_FUNCREF
 typedef struct {
-    int		fr_func;	// function index
+    int		fr_dfunc_idx;	// function index for :def function
+    char_u	*fr_func_name;	// function name for legacy function
 } funcref_T;
 
 // arguments to ISN_NEWFUNC