diff --git a/include/libtorrent/utp_stream.hpp b/include/libtorrent/utp_stream.hpp
index 7105fbda6..2c05f81a7 100644
--- a/include/libtorrent/utp_stream.hpp
+++ b/include/libtorrent/utp_stream.hpp
@@ -63,7 +63,7 @@ namespace libtorrent
 	#define TORRENT_VERBOSE_UTP_LOG 1
 #endif
 
-#ifdef TORRENT_UTP_LOG
+#if TORRENT_UTP_LOG
 	bool is_utp_stream_logging();
 
 	// This function should be used at the very beginning and very end of your program.