commit 6d7433d44c7f18cd84d2de105beb5c646ed0e355
Author: Adriaan de Groot <groot@kde.org>
Date:   Tue Apr 24 19:15:32 2018 +0200

    QTimer may not be an incomplete type as it is used as a member variable.
    Add the #include to fully define the type. This problem shows up when this
    header is included in a context that doesn't already have QTimer included --
    CMake 3.11 exposes that accidentally.
    
    Upstreamed from FreeBSD ports.

diff --git a/ktorrent/dialogs/torrentcreatordlg.h b/ktorrent/dialogs/torrentcreatordlg.h
index 68dde8ad..12a1a433 100644
--- a/ktorrent/dialogs/torrentcreatordlg.h
+++ b/ktorrent/dialogs/torrentcreatordlg.h
@@ -23,6 +23,8 @@
 #define KT_TORRENTCREATORDLG_HH
 
 #include <QDialog>
+#include <QTimer>
+
 #include "ui_torrentcreatordlg.h"
 #include <torrent/torrentcreator.h>