diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/debug/Frame-03.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/debug/Frame-03.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,19 @@
+// When the debugger is triggered from different stack frames that happen to
+// occupy the same memory, it delivers different Debugger.Frame objects.
+
+var g = newGlobal();
+var dbg = Debugger(g);
+var hits;
+var a = [];
+dbg.onDebuggerStatement = function (frame) {
+    for (var i = 0; i < a.length; i++) 
+        assertEq(a[i] === frame, false);
+    a.push(frame);
+    hits++;
+};
+
+g.eval("function f() { debugger; }");
+g.eval("function h() { debugger; f(); }");
+hits = 0;
+g.eval("for (var i = 0; i < 4; i++) h();");
+assertEq(hits, 8);