diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/sharedbuf/is-zeroed.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/sharedbuf/is-zeroed.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,12 @@
+// Test that the SharedArrayBuffer memory is properly zeroed.
+
+function f() {
+    var x = new SharedArrayBuffer(4096);
+    var y = new Int32Array(x);
+    assertEq(y[0], 0);
+    assertEq(y[1], 0);
+    assertEq(y[1023], 0);
+}
+
+if (typeof SharedArrayBuffer !== "undefined")
+    f();