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diff --git a/src/test/ui/run-pass/issues/issue-20055-box-trait.rs b/src/test/ui/run-pass/issues/issue-20055-box-trait.rs
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+++ b/src/test/ui/run-pass/issues/issue-20055-box-trait.rs
@@ -0,0 +1,50 @@
+// Copyright 2015 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.
+
+// See Issues #20055 and #21695.
+
+// We are checking here that the temporaries `Box<[i8, k]>`, for `k`
+// in 1, 2, 3, 4, that are induced by the match expression are
+// properly handled, in that only *one* will be initialized by
+// whichever arm is run, and subsequently dropped at the end of the
+// statement surrounding the `match`.
+
+trait Boo {
+    fn dummy(&self) { }
+}
+
+impl Boo for [i8; 1] { }
+impl Boo for [i8; 2] { }
+impl Boo for [i8; 3] { }
+impl Boo for [i8; 4] { }
+
+pub fn foo(box_1: fn () -> Box<[i8; 1]>,
+           box_2: fn () -> Box<[i8; 2]>,
+           box_3: fn () -> Box<[i8; 3]>,
+           box_4: fn () -> Box<[i8; 4]>,
+            ) {
+    println!("Hello World 1");
+    let _: Box<Boo> = match 3 {
+        1 => box_1(),
+        2 => box_2(),
+        3 => box_3(),
+        _ => box_4(),
+    };
+    println!("Hello World 2");
+}
+
+pub fn main() {
+    fn box_1() -> Box<[i8; 1]> { Box::new( [1; 1] ) }
+    fn box_2() -> Box<[i8; 2]> { Box::new( [1; 2] ) }
+    fn box_3() -> Box<[i8; 3]> { Box::new( [1; 3] ) }
+    fn box_4() -> Box<[i8; 4]> { Box::new( [1; 4] ) }
+
+    foo(box_1, box_2, box_3, box_4);
+}