diff --git a/ndn-cpp/data.hpp b/ndn-cpp/data.hpp
index 0b0dd3e..5bf1e60 100644
--- a/ndn-cpp/data.hpp
+++ b/ndn-cpp/data.hpp
@@ -4,7 +4,7 @@
  */
 
 #ifndef NDN_DATA_HPP
-#define	NDN_DATA_HPP
+#define NDN_DATA_HPP
 
 #include "name.hpp"
 #include "publisher-public-key-digest.hpp"