diff -r 000000000000 -r 6474c204b198 js/src/tests/js1_8_5/regress/regress-554955-6.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/tests/js1_8_5/regress/regress-554955-6.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,47 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/licenses/publicdomain/
+ */
+
+var v="global";
+function f(a) {
+  // This eval could extend f's call object. However, the call object has
+  // not yet been marked as a delegate at this point, so no scope chain
+  // purge takes place when it is extended.
+  eval(a);
+  let (b=3) {
+    // This eval causes the cloned block object to be added to the
+    // scope chain. The block needs a unique shape: its parent call
+    // could acquire bindings for anything without affecting the global
+    // object's shape, so it's up to the block's shape to mismatch all
+    // property cache entries for prior blocks.
+    eval("");
+    return v;
+  };
+}
+
+// Call the function once, to cache a reference to the global v from within
+// f's lexical block.
+assertEq("global", f(""));
+
+// Call the function again, adding a binding to the call, and ensure that
+// we do not see any property cache entry created by the previous reference
+// that would direct us to the global definition.
+assertEq("local", f("var v='local'"));
+
+// Similarly,but with a doubly-nested block; make sure everyone gets marked.
+function f2(a) {
+  eval(a);
+  let (b=3) {
+    let (c=4) {
+      eval("");
+      return v;
+    };
+  };
+}
+
+assertEq("global", f2(""));
+assertEq("local",  f2("var v='local'"));
+
+reportCompare(true, true);