diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/ion/bug939868.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/ion/bug939868.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,3 @@
+function f(x, y) { return x || Math.fround(y); }
+assertEq(f(0, 0), 0);
+assertEq(f(0xfffffff, 0), 0xfffffff);