diff --git a/test/401-optimizing-compiler/src/Main.java b/test/401-optimizing-compiler/src/Main.java
index 7c3fd25..a1e62b3 100644
--- a/test/401-optimizing-compiler/src/Main.java
+++ b/test/401-optimizing-compiler/src/Main.java
@@ -110,6 +110,11 @@
     if (result != 42) {
       throw new Error("Unexpected result: " + result);
     }
+
+    String s = $opt$StringInit();
+    if (!s.equals("hello world")) {
+      throw new Error("Unexpected string: " + s);
+    }
   }
 
   public static void invokePrivate() {
@@ -230,5 +235,9 @@
     return array.length;
   }
 
+  public static String $opt$StringInit() {
+    return new String("hello world");
+  }
+
   Object o;
 }