src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/codegen/OptimisticTypesCalculator.java

@@ -128,11 +128,11 @@
         return true;
     }
 
     @Override
     public boolean enterForNode(final ForNode forNode) {
-        if(forNode.isForIn()) {
+        if(forNode.isForInOrOf()) {
             // for..in has the iterable in its "modify"
             tagNeverOptimistic(forNode.getModify());
         } else {
             // Test is never optimistic (always coerced to boolean).
             tagNeverOptimisticLoopTest(forNode);