diff --git a/include/llog.h b/include/llog.h
index 7e6676b..2d068f1 100644
--- a/include/llog.h
+++ b/include/llog.h
@@ -227,6 +227,8 @@ static inline size_t log_fill_head_str(int level, char* log, size_t szlog,
 	return szbuf;
 }
 
+extern void log_buf(void);
+
 #ifdef __cplusplus
 }
 #endif