diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/basic/testIncDec.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/basic/testIncDec.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,19 @@
+function testIncDec2(ii) {
+    var x = [];
+    for (let j=0;j<5;++j) {
+        ii=j;
+        jj=j;
+        var kk=j;
+        x.push(ii--);
+        x.push(jj--);
+        x.push(kk--);
+        x.push(++ii);
+        x.push(++jj);
+        x.push(++kk);
+    }
+    return x.join(",");
+}
+function testIncDec() {
+    return testIncDec2(0);
+}
+assertEq(testIncDec(), "0,0,0,0,0,0,1,1,1,1,1,1,2,2,2,2,2,2,3,3,3,3,3,3,4,4,4,4,4,4");