diff -r 000000000000 -r 6474c204b198 js/src/tests/ecma_3/FunExpr/regress-545980.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/tests/ecma_3/FunExpr/regress-545980.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,41 @@
+/*
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/licenses/publicdomain/
+ */
+
+var BUGNUMBER = 518103;
+var summary = 'partial flat closures must not reach across funargs';
+var actual = "no crash";
+var expect = actual;
+
+function Timer(){}
+Timer.prototype = { initWithCallback: function (o) {Timer.q.push(o)} };
+Timer.q = [];
+
+var later;
+var ac = {startSearch: function(q,s,n,o){later=o}};
+
+var bm = {insertBookmark: function(){}, getIdForItemAt: function(){}};
+
+function run_test() {
+  var tagIds = [];
+
+  (function doSearch(query) {
+    ac.startSearch(query, "", null, {
+      onSearchResult: function() {
+        var num = tagIds.length;
+
+        var timer = new Timer;
+        var next = query.slice(1);
+        timer.initWithCallback({ notify: function() doSearch(next) });
+      }
+    });
+  })("title");
+}
+
+run_test();
+later.onSearchResult();
+for (var i in Timer.q)
+  Timer.q[i].notify();
+
+reportCompare(expect, actual, summary);