diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/ion/bug839315.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/ion/bug839315.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,18 @@
+function f(x) {
+    switch(x) {
+      case 0:
+      case 100:
+    }
+}
+f("");
+evaluate('f({})', { noScriptRval : true });
+
+function g(x) {
+    switch(x) {
+      case 0.1:
+      case 100:
+    }
+}
+
+g(false);
+evaluate('g({})', { noScriptRval : true });