diff --git a/src/proto/buffer.pro b/src/proto/buffer.pro
index e9a37de..a671075 100644
--- a/src/proto/buffer.pro
+++ b/src/proto/buffer.pro
@@ -55,6 +55,7 @@
 void write_viminfo_bufferlist(FILE *fp);
 int bt_quickfix(buf_T *buf);
 int bt_terminal(buf_T *buf);
+int bt_help(buf_T *buf);
 int bt_nofile(buf_T *buf);
 int bt_dontwrite(buf_T *buf);
 int bt_dontwrite_msg(buf_T *buf);