diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/jaeger/bug646938.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/jaeger/bug646938.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,21 @@
+function f() {
+    var x = -[NaN][0];
+    assertEq(x === x, false);
+    assertEq(x !== x, true);
+    assertEq(x == x, false);
+    assertEq(x != x, true);
+
+    var y = -("x" / {});
+    var z = y;
+    assertEq(y === z, false);
+    assertEq(y !== z, true);
+    assertEq(y == z, false);
+    assertEq(y != z, true);
+}
+f();
+
+function g(x, y) {
+    var z = x / y;
+    assertEq(z === z, false);
+}
+g(0, 0);