--- lib/EWMH.cc.orig	2005-01-24 08:50:56.000000000 +0100
+++ lib/EWMH.cc	2018-03-18 12:14:59.969608000 +0100
@@ -247,7 +247,7 @@
 
 void bt::EWMH::setDesktopViewport(Window target, int x, int y) const {
   const unsigned long viewport[] =
-    { static_cast<long>(x), static_cast<long>(y) };
+    { static_cast<unsigned long>(x), static_cast<unsigned long>(y) };
   setProperty(target, XA_CARDINAL, net_desktop_viewport,
               reinterpret_cast<const unsigned char *>(viewport), 2);
 }