diff --git a/src/gui/kernel/qinputdevicemanager_p_p.h b/src/gui/kernel/qinputdevicemanager_p_p.h
index 871f9315c3..82a86446a0 100644
--- a/src/gui/kernel/qinputdevicemanager_p_p.h
+++ b/src/gui/kernel/qinputdevicemanager_p_p.h
@@ -69,7 +69,7 @@ public:
     int deviceCount(QInputDeviceManager::DeviceType type) const;
     void setDeviceCount(QInputDeviceManager::DeviceType type, int count);
 
-    std::array<int, QInputDeviceManager::NumDeviceTypes> m_deviceCount;
+    std::array<int, QInputDeviceManager::NumDeviceTypes> m_deviceCount = {};
 
     Qt::KeyboardModifiers keyboardModifiers;
 };