diff --git a/src/vim9execute.c b/src/vim9execute.c
index d357fc4..882b13c 100644
--- a/src/vim9execute.c
+++ b/src/vim9execute.c
@@ -398,6 +398,9 @@
 	if (argv[i].v_type == VAR_SPECIAL
 		&& argv[i].vval.v_number == VVAL_NONE)
 	    continue;
+	// only pass values to user functions, never types
+	if (check_typval_is_value(&argv[i]) == FAIL)
+	    return FAIL;
 
 	if (i < ufunc->uf_args.ga_len && ufunc->uf_arg_types != NULL)
 	    type = ufunc->uf_arg_types[i];
@@ -4462,6 +4465,12 @@
 		    garray_T	*trystack = &ectx->ec_trystack;
 		    trycmd_T    *trycmd = NULL;
 
+		    ///////////////////////////////////////////////////
+		    // TODO: If FAIL, line number in output not correct
+		    ///////////////////////////////////////////////////
+		    if (check_typval_is_value(STACK_TV_BOT(-1)) == FAIL)
+			goto theend;
+
 		    if (trystack->ga_len > 0)
 			trycmd = ((trycmd_T *)trystack->ga_data)
 							+ trystack->ga_len - 1;