diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/basic/testBug648438.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/basic/testBug648438.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,7 @@
+for (var i = 0; i < 20; i++) {
+    (function () {
+        try {
+            JSON.parse();
+        } catch (e) {}
+    }).call();
+}