diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/ion/bug779125.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/ion/bug779125.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,7 @@
+function test() {
+    for (var i = 0; i < 60; i++) {
+        x = ''.charAt(-1);
+        assertEq(x, "");
+    }
+}
+test();