diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/ion/bug743099.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/ion/bug743099.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,9 @@
+function Day( t ) {}
+function WeekDay( t ) {
+  var weekday = (Day(t)+4) % 7;
+  return( weekday < 0 ? 7 + weekday : weekday );
+}
+var expect = 'No Error';
+for (var i = 0; i < 50; i++) {
+    var [] = expect ? WeekDay( i.a ) : true, uneval;
+}