diff --git a/src/DefaultBtProgressInfoFile.cc b/src/DefaultBtProgressInfoFile.cc
index 9d03e3e9..7907284f 100644
--- a/src/DefaultBtProgressInfoFile.cc
+++ b/src/DefaultBtProgressInfoFile.cc
@@ -57,6 +57,7 @@
 #include "DownloadContext.h"
 #include "BufferedFile.h"
 #include "SHA1IOFile.h"
+#include "BtConstants.h"
 #ifdef ENABLE_BITTORRENT
 #  include "PeerStorage.h"
 #  include "BtRuntime.h"