diff -r 000000000000 -r 6474c204b198 js/src/tests/ecma/extensions/trapflatclosure.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/tests/ecma/extensions/trapflatclosure.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,26 @@
+// |reftest| require-or(debugMode,skip)
+/*
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/licenses/publicdomain/
+ */
+
+var BUGNUMBER = 549617;
+var summary = 'flat closure debugged via trap while still active';
+
+var expect = "abc";
+var actual = expect;
+
+function a(x, y) {
+    return function () { return x; };
+}
+
+var f = a("abc", 123);
+if (this.trap && this.setDebug) {
+    setDebug(true);
+    trap(f, "try {actual = x} catch (e) {actual = e}");
+}
+f();
+
+reportCompare(expect, actual, summary);
+
+printStatus("All tests passed!");