diff --git a/dbms/programs/server/TCPHandler.h b/dbms/programs/server/TCPHandler.h
index 98b76268047..19641e88d25 100644
--- a/dbms/programs/server/TCPHandler.h
+++ b/dbms/programs/server/TCPHandler.h
@@ -25,7 +25,7 @@ namespace Poco { class Logger; }
 namespace DB
 {
 
-class ColumnsDescription;
+struct ColumnsDescription;
 
 /// State of query processing.
 struct QueryState