diff --git a/Keymaster.h b/Keymaster.h
index 7571402..fabe0f4 100644
--- a/Keymaster.h
+++ b/Keymaster.h
@@ -117,6 +117,7 @@
   private:
     std::unique_ptr<KmDevice> mDevice;
     DISALLOW_COPY_AND_ASSIGN(Keymaster);
+    static bool hmacKeyGenerated;
 };
 
 }  // namespace vold