// option. This file may not be copied, modified, or distributed
// except according to those terms.
-// pretty-expanded FIXME #23616
-
#![allow(unknown_features)]
#![feature(box_syntax)]
--- /dev/null
+// Copyright 2016 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.
+
+// compile-flags:--test
+// should-fail
+
+#![doc(test(attr(deny(warnings))))]
+
+/// ```no_run
+/// let a = 3;
+/// ```
+pub fn foo() {}