Interpreter test for @objc unowned reference.

Swift SVN r21076

Author: jckarter

test/Interpreter/SDK/objc_unowned.swift

@@ -0,0 +1,9 @@
+// RUN: %target-run-simple-swift | FileCheck %s
+
+import Foundation
+
+let x = NSObject()
+unowned let y = x
+
+println(y) // CHECK:      <NSObject: [[ID:.*]]>
+println(x) // CHECK-NEXT: <NSObject: [[ID]]>