added unit and standalone test for 15221, extra debugging output

src/test/run-pass/issue-15221.rs

@@ -0,0 +1,22 @@
+// Copyright 2014 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+#![feature(macro_rules)]
+
+macro_rules! inner_bind (
+    ( $p:pat, $id:ident) => ({let $p = 13; $id}))
+
+macro_rules! outer_bind (
+    ($p:pat, $id:ident ) => (inner_bind!($p, $id)))
+
+fn main() {
+    outer_bind!(g1,g1);
+}
+