diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/debug/Frame-eval-10.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/debug/Frame-eval-10.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,13 @@
+// frame.eval returns null if the eval code fails with an uncatchable error.
+
+var g = newGlobal();
+var dbg = Debugger(g);
+var hits = 0;
+dbg.onDebuggerStatement = function (frame) {
+    if (hits++ === 0)
+        assertEq(frame.eval("debugger;"), null);
+    else
+        return null;
+};
+assertEq(g.eval("debugger; 'ok';"), "ok");
+assertEq(hits, 2);