diff --git a/src/prevector.h b/src/prevector.h
--- a/src/prevector.h
+++ b/src/prevector.h
@@ -2,8 +2,8 @@
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
-#ifndef _BITCOIN_PREVECTOR_H_
-#define _BITCOIN_PREVECTOR_H_
+#ifndef BITCOIN_PREVECTOR_H
+#define BITCOIN_PREVECTOR_H
 
 #include <cassert>
 #include <cstdint>
@@ -582,4 +582,4 @@
 };
 #pragma pack(pop)
 
-#endif
+#endif // BITCOIN_PREVECTOR_H