diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/debug/Object-identity-03.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/debug/Object-identity-03.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,25 @@
+// The same object gets the same Debugger.Object wrapper at different times, if the difference would be observable.
+
+var N = 12;
+
+var g = newGlobal();
+var dbg = Debugger(g);
+var wrappers = [];
+
+dbg.onDebuggerStatement = function (frame) { wrappers.push(frame.arguments[0]); };
+g.eval("var originals = []; function f(x) { originals.push(x); debugger; }");
+for (var i = 0; i < N; i++)
+    g.eval("f({});");
+assertEq(wrappers.length, N);
+
+for (var i = 0; i < N; i++)
+    for (var j = i + 1; j < N; j++)
+        assertEq(wrappers[i] === wrappers[j], false);
+
+gc();
+
+dbg.onDebuggerStatement = function (frame) { assertEq(frame.arguments[0], wrappers.pop()); };
+g.eval("function h(x) { debugger; }");
+for (var i = 0; i < N; i++)
+    g.eval("h(originals.pop());");
+assertEq(wrappers.length, 0);