diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/debug/Frame-offset-02.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/debug/Frame-offset-02.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,16 @@
+// frame.offset gives different values at different points in a script.
+
+var g = newGlobal();
+var dbg = Debugger(g);
+var s = undefined, a = []
+dbg.onDebuggerStatement = function (frame) {
+    if (s === undefined)
+        s = frame.script;
+    else
+        assertEq(s, frame.script);
+    assertEq(frame.offset !== undefined, true);
+    assertEq(a.indexOf(frame.offset), -1);
+    a.push(frame.offset);
+};
+g.eval("debugger; debugger; debugger;");
+assertEq(a.length, 3);