auto merge of #11914 : FlaPer87/rust/issue-6157, r=alexcrichton

closes #6157

src/test/run-pass/issue-6157.rs

@@ -0,0 +1,30 @@
+// 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.
+
+pub trait OpInt<'a> { fn call<'a>(&'a self, int, int) -> int; }
+
+impl<'a> OpInt<'a> for 'a |int, int| -> int {
+    fn call(&self, a:int, b:int) -> int {
+        (*self)(a, b)
+    }
+}
+
+fn squarei<'a>(x: int, op: &'a OpInt) -> int { op.call(x, x) }
+
+fn muli(x:int, y:int) -> int { x * y }
+
+pub fn main() {
+    let f = |x,y| muli(x,y);
+    {
+        let g = &f;
+        let h = g as &OpInt;
+        squarei(3, h);
+    }
+}