diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/debug/onExceptionUnwind-07.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/debug/onExceptionUnwind-07.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,15 @@
+// Unwinding due to uncatchable errors does not trigger onExceptionUnwind.
+
+var g = newGlobal();
+var dbg = Debugger(g);
+var hits = 0;
+dbg.onExceptionUnwind = function (frame, value) { hits = 'BAD'; };
+dbg.onDebuggerStatement = function (frame) {
+    if (hits++ === 0)
+        assertEq(frame.eval("debugger;"), null);
+    else
+        return null;
+}
+
+assertEq(g.eval("debugger; 2"), 2);
+assertEq(hits, 2);