diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/ion/string-concat-short.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/ion/string-concat-short.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,13 @@
+function f() {
+    var res = 0;
+    for (var i=0; i<100; i++) {
+	var s = "test" + i;
+	res += s.length;
+	assertEq(s[0], "t");
+	assertEq(s[3], "t");
+	if (i > 90)
+	    assertEq(s[4], "9");
+    }
+    return res;
+}
+assertEq(f(), 590);