Fix uninitialized value access

src/tree.c

@@ -135,7 +135,7 @@ static void irjp_copy_node_data(RJP_tree_node *restrict dest, RJP_tree_node *res
 	dest->data = src->data;
 }
 static RJP_tree_node* irjp_clone_node(const RJP_tree_node* src, RJP_tree_node* parent){
-	RJP_tree_node* dest = rjp_alloc(sizeof(RJP_tree_node));
+	RJP_tree_node* dest = rjp_calloc(1, sizeof(RJP_tree_node));
 	rjp_copy_value(&dest->data.value, &src->data.value);
 	irjp_strcpy(&dest->data.name, &src->data.name);
 	dest->parent = parent;