diff --git a/src/plugins/platforms/xcb/qxcbconnection_xi2.cpp b/src/plugins/platforms/xcb/qxcbconnection_xi2.cpp
index 969b6deed0..81cdaa56c5 100644
--- a/src/plugins/platforms/xcb/qxcbconnection_xi2.cpp
+++ b/src/plugins/platforms/xcb/qxcbconnection_xi2.cpp
@@ -38,6 +38,7 @@
 #include "qtouchdevice.h"
 #include <qpa/qwindowsysteminterface.h>
 #include <QDebug>
+#include <cmath>
 
 #ifdef XCB_USE_XINPUT2