diff --git a/js/js.tests/test/org/jetbrains/kotlin/js/test/rhino/RhinoUtils.java b/js/js.tests/test/org/jetbrains/kotlin/js/test/rhino/RhinoUtils.java
index fe73f3f5c04..ebe8d8b21ff 100644
--- a/js/js.tests/test/org/jetbrains/kotlin/js/test/rhino/RhinoUtils.java
+++ b/js/js.tests/test/org/jetbrains/kotlin/js/test/rhino/RhinoUtils.java
@@ -109,6 +109,7 @@ public final class RhinoUtils {
         catch (IOException e) {
             throw new RuntimeException(e);
         }
+        context.setOptimizationLevel(-1);
         context.evaluateString(scope, result, inputFile, 1, null);
     }