diff --git a/src/vim9expr.c b/src/vim9expr.c
index 6affac2..d36df84 100644
--- a/src/vim9expr.c
+++ b/src/vim9expr.c
@@ -759,7 +759,7 @@
 
 	    if (STRCMP(name, "add") == 0 && argcount == 2)
 	    {
-		type_T	    *type = get_type_on_stack(cctx, 1);
+		type_T	    *type = get_decl_type_on_stack(cctx, 1);
 
 		// add() can be compiled to instructions if we know the type
 		if (type->tt_type == VAR_LIST)