diff --git a/src/plugins/platforms/wayland/qwaylandclipboard_p.h b/src/plugins/platforms/wayland/qwaylandclipboard_p.h
index 28336202241..42202285967 100644
--- a/src/plugins/platforms/wayland/qwaylandclipboard_p.h
+++ b/src/plugins/platforms/wayland/qwaylandclipboard_p.h
@@ -78,7 +78,7 @@ public:
     bool ownsMode(QClipboard::Mode mode) const override;
 
 private:
-    QWaylandDisplay *mDisplay;
+    QWaylandDisplay *mDisplay = nullptr;
     QMimeData m_emptyData;
 };
 
diff --git a/src/plugins/platforms/wayland/qwaylandcursor_p.h b/src/plugins/platforms/wayland/qwaylandcursor_p.h
index 916a464e455..b7b1c2a75e0 100644
--- a/src/plugins/platforms/wayland/qwaylandcursor_p.h
+++ b/src/plugins/platforms/wayland/qwaylandcursor_p.h
@@ -119,8 +119,8 @@ private:
 
     struct wl_cursor* requestCursor(WaylandCursor shape);
     void initCursorMap();
-    QWaylandDisplay *mDisplay;
-    struct wl_cursor_theme *mCursorTheme;
+    QWaylandDisplay *mDisplay = nullptr;
+    struct wl_cursor_theme *mCursorTheme = nullptr;
     QPoint mLastPos;
     QMap<WaylandCursor, wl_cursor *> mCursors;
     QMultiMap<WaylandCursor, QByteArray> mCursorNamesMap;
diff --git a/src/plugins/platforms/wayland/qwaylanddatadevice.cpp b/src/plugins/platforms/wayland/qwaylanddatadevice.cpp
index 4411ba65ccd..300c9de0aa8 100644
--- a/src/plugins/platforms/wayland/qwaylanddatadevice.cpp
+++ b/src/plugins/platforms/wayland/qwaylanddatadevice.cpp
@@ -203,7 +203,7 @@ void QWaylandDataDevice::data_device_motion(uint32_t time, wl_fixed_t x, wl_fixe
 
     m_dragPoint = calculateDragPosition(x, y, m_dragWindow);
 
-    QMimeData *dragData;
+    QMimeData *dragData = nullptr;
     Qt::DropActions supportedActions;
     if (drag) {
         dragData = drag->mimeData();
diff --git a/src/plugins/platforms/wayland/qwaylanddatadevicemanager_p.h b/src/plugins/platforms/wayland/qwaylanddatadevicemanager_p.h
index 3daf780aaa9..10df1bca912 100644
--- a/src/plugins/platforms/wayland/qwaylanddatadevicemanager_p.h
+++ b/src/plugins/platforms/wayland/qwaylanddatadevicemanager_p.h
@@ -76,7 +76,7 @@ public:
     QWaylandDisplay *display() const;
 
 private:
-    QWaylandDisplay *m_display;
+    QWaylandDisplay *m_display = nullptr;
 };
 
 }
diff --git a/src/plugins/platforms/wayland/qwaylanddataoffer_p.h b/src/plugins/platforms/wayland/qwaylanddataoffer_p.h
index c9b9c21f17d..932506bf51a 100644
--- a/src/plugins/platforms/wayland/qwaylanddataoffer_p.h
+++ b/src/plugins/platforms/wayland/qwaylanddataoffer_p.h
@@ -98,8 +98,8 @@ protected:
 private:
     int readData(int fd, QByteArray &data) const;
 
-    mutable QWaylandDataOffer *m_dataOffer;
-    QWaylandDisplay *m_display;
+    mutable QWaylandDataOffer *m_dataOffer = nullptr;
+    QWaylandDisplay *m_display = nullptr;
     mutable QStringList m_types;
     mutable QHash<QString, QByteArray> m_data;
 };
diff --git a/src/plugins/platforms/wayland/qwaylanddatasource_p.h b/src/plugins/platforms/wayland/qwaylanddatasource_p.h
index bba003f561b..a79cdcbfa1a 100644
--- a/src/plugins/platforms/wayland/qwaylanddatasource_p.h
+++ b/src/plugins/platforms/wayland/qwaylanddatasource_p.h
@@ -86,8 +86,8 @@ protected:
     void data_source_target(const QString &mime_type) override;
 
 private:
-    QWaylandDisplay *m_display;
-    QMimeData *m_mime_data;
+    QWaylandDisplay *m_display = nullptr;
+    QMimeData *m_mime_data = nullptr;
 };
 
 }
diff --git a/src/plugins/platforms/wayland/qwaylanddisplay_p.h b/src/plugins/platforms/wayland/qwaylanddisplay_p.h
index 0a7ea427a5d..dbcc2112f46 100644
--- a/src/plugins/platforms/wayland/qwaylanddisplay_p.h
+++ b/src/plugins/platforms/wayland/qwaylanddisplay_p.h
@@ -149,7 +149,7 @@ public:
         uint32_t id;
         QString interface;
         uint32_t version;
-        struct ::wl_registry *registry;
+        struct ::wl_registry *registry = nullptr;
         RegistryGlobal(uint32_t id_, const QString &interface_, uint32_t version_, struct ::wl_registry *registry_)
             : id(id_), interface(interface_), version(version_), registry(registry_) { }
     };
@@ -191,17 +191,17 @@ private:
     void requestWaylandSync();
 
     struct Listener {
-        RegistryListener listener;
-        void *data;
+        RegistryListener listener = nullptr;
+        void *data = nullptr;
     };
 
-    struct wl_display *mDisplay;
+    struct wl_display *mDisplay = nullptr;
     QtWayland::wl_compositor mCompositor;
     QScopedPointer<QWaylandShm> mShm;
     QList<QWaylandScreen *> mScreens;
     QList<QWaylandInputDevice *> mInputDevices;
     QList<Listener> mRegistryListeners;
-    QWaylandIntegration *mWaylandIntegration;
+    QWaylandIntegration *mWaylandIntegration = nullptr;
 #if QT_CONFIG(wayland_datadevice)
     QScopedPointer<QWaylandDataDeviceManager> mDndSelectionHandler;
 #endif
@@ -212,7 +212,7 @@ private:
     QScopedPointer<QWaylandWindowManagerIntegration> mWindowManagerIntegration;
     QScopedPointer<QtWayland::zwp_text_input_manager_v2> mTextInputManager;
     QScopedPointer<QWaylandHardwareIntegration> mHardwareIntegration;
-    QSocketNotifier *mReadNotifier;
+    QSocketNotifier *mReadNotifier = nullptr;
     int mFd;
     int mWritableNotificationFd;
     QList<RegistryGlobal> mGlobals;
diff --git a/src/plugins/platforms/wayland/qwaylanddnd_p.h b/src/plugins/platforms/wayland/qwaylanddnd_p.h
index 8a1d7f1f1ef..0f14eb00be2 100644
--- a/src/plugins/platforms/wayland/qwaylanddnd_p.h
+++ b/src/plugins/platforms/wayland/qwaylanddnd_p.h
@@ -84,7 +84,7 @@ protected:
 
 
 private:
-    QWaylandDisplay *m_display;
+    QWaylandDisplay *m_display = nullptr;
 };
 #endif
 }
diff --git a/src/plugins/platforms/wayland/qwaylandextendedsurface_p.h b/src/plugins/platforms/wayland/qwaylandextendedsurface_p.h
index 02700b2901d..dffd04281f6 100644
--- a/src/plugins/platforms/wayland/qwaylandextendedsurface_p.h
+++ b/src/plugins/platforms/wayland/qwaylandextendedsurface_p.h
@@ -83,7 +83,7 @@ private:
     void extended_surface_set_generic_property(const QString &name, wl_array *value) override;
     void extended_surface_close() override;
 
-    QWaylandWindow *m_window;
+    QWaylandWindow *m_window = nullptr;
     QVariantMap m_properties;
 };
 
diff --git a/src/plugins/platforms/wayland/qwaylandinputcontext_p.h b/src/plugins/platforms/wayland/qwaylandinputcontext_p.h
index a554f23011c..cbb2e18dc75 100644
--- a/src/plugins/platforms/wayland/qwaylandinputcontext_p.h
+++ b/src/plugins/platforms/wayland/qwaylandinputcontext_p.h
@@ -107,7 +107,7 @@ protected:
 private:
     Qt::KeyboardModifiers modifiersToQtModifiers(uint32_t modifiers);
 
-    QWaylandDisplay *m_display;
+    QWaylandDisplay *m_display = nullptr;
     QWaylandInputMethodEventBuilder m_builder;
 
     QVector<Qt::KeyboardModifier> m_modifiersMap;
@@ -155,7 +155,7 @@ public:
 private:
     QWaylandTextInput *textInput() const;
 
-    QWaylandDisplay *mDisplay;
+    QWaylandDisplay *mDisplay = nullptr;
     QPointer<QWindow> mCurrentWindow;
 };
 
diff --git a/src/plugins/platforms/wayland/qwaylandinputdevice_p.h b/src/plugins/platforms/wayland/qwaylandinputdevice_p.h
index 8a02769e3bb..2c7d2cffd61 100644
--- a/src/plugins/platforms/wayland/qwaylandinputdevice_p.h
+++ b/src/plugins/platforms/wayland/qwaylandinputdevice_p.h
@@ -143,13 +143,13 @@ public:
 private:
     void setCursor(Qt::CursorShape cursor, QWaylandScreen *screen);
 
-    QWaylandDisplay *mQDisplay;
-    struct wl_display *mDisplay;
+    QWaylandDisplay *mQDisplay = nullptr;
+    struct wl_display *mDisplay = nullptr;
 
     int mVersion;
     uint32_t mCaps = 0;
 
-    struct wl_surface *pointerSurface;
+    struct wl_surface *pointerSurface = nullptr;
 
 #if QT_CONFIG(wayland_datadevice)
     QWaylandDataDevice *mDataDevice = nullptr;
@@ -207,7 +207,7 @@ public:
                             uint32_t mods_locked,
                             uint32_t group) override;
 
-    QWaylandInputDevice *mParent;
+    QWaylandInputDevice *mParent = nullptr;
     QPointer<QWaylandWindow> mFocus;
 #if QT_CONFIG(xkbcommon_evdev)
     xkb_context *mXkbContext = nullptr;
@@ -262,7 +262,7 @@ public:
 
     void releaseButtons();
 
-    QWaylandInputDevice *mParent;
+    QWaylandInputDevice *mParent = nullptr;
     QPointer<QWaylandWindow> mFocus;
     uint32_t mEnterSerial = 0;
 #if QT_CONFIG(cursor)
@@ -302,7 +302,7 @@ public:
     bool allTouchPointsReleased();
     void releasePoints();
 
-    QWaylandInputDevice *mParent;
+    QWaylandInputDevice *mParent = nullptr;
     QPointer<QWaylandWindow> mFocus;
     QList<QWindowSystemInterface::TouchPoint> mTouchPoints;
     QList<QWindowSystemInterface::TouchPoint> mPrevTouchPoints;
diff --git a/src/plugins/platforms/wayland/qwaylandnativeinterface_p.h b/src/plugins/platforms/wayland/qwaylandnativeinterface_p.h
index c83180c0995..3de80eb6ac4 100644
--- a/src/plugins/platforms/wayland/qwaylandnativeinterface_p.h
+++ b/src/plugins/platforms/wayland/qwaylandnativeinterface_p.h
@@ -85,7 +85,7 @@ public:
     QFunctionPointer platformFunction(const QByteArray &resource) const override;
 
 private:
-    QWaylandIntegration *m_integration;
+    QWaylandIntegration *m_integration = nullptr;
     QHash<QPlatformWindow*, QVariantMap> m_windowProperties;
 
     static void setSync(QWindow *window);
diff --git a/src/plugins/platforms/wayland/qwaylandqtkey_p.h b/src/plugins/platforms/wayland/qwaylandqtkey_p.h
index 3374b907a44..9091cf81935 100644
--- a/src/plugins/platforms/wayland/qwaylandqtkey_p.h
+++ b/src/plugins/platforms/wayland/qwaylandqtkey_p.h
@@ -68,7 +68,7 @@ public:
     QWaylandQtKeyExtension(QWaylandDisplay *display, uint32_t id);
 
 private:
-    QWaylandDisplay *m_display;
+    QWaylandDisplay *m_display = nullptr;
 
     void key_extension_qtkey(struct wl_surface *surface,
                              uint32_t time,
diff --git a/src/plugins/platforms/wayland/qwaylandshellsurface_p.h b/src/plugins/platforms/wayland/qwaylandshellsurface_p.h
index 06d92ba086a..3a725d822f8 100644
--- a/src/plugins/platforms/wayland/qwaylandshellsurface_p.h
+++ b/src/plugins/platforms/wayland/qwaylandshellsurface_p.h
@@ -104,7 +104,7 @@ protected:
     virtual void setMinimized() {}
 
 private:
-    QWaylandWindow *m_window;
+    QWaylandWindow *m_window = nullptr;
     friend class QWaylandWindow;
 };
 
diff --git a/src/plugins/platforms/wayland/qwaylandsubsurface_p.h b/src/plugins/platforms/wayland/qwaylandsubsurface_p.h
index 36a92a7559e..a9fd76a887d 100644
--- a/src/plugins/platforms/wayland/qwaylandsubsurface_p.h
+++ b/src/plugins/platforms/wayland/qwaylandsubsurface_p.h
@@ -86,8 +86,8 @@ private:
     // to keep track of the sync state
     void set_sync();
     void set_desync();
-    QWaylandWindow *m_window;
-    QWaylandWindow *m_parent;
+    QWaylandWindow *m_window = nullptr;
+    QWaylandWindow *m_parent = nullptr;
     bool m_synchronized = false;
     QMutex m_syncLock;
 
diff --git a/src/plugins/platforms/wayland/qwaylandtouch_p.h b/src/plugins/platforms/wayland/qwaylandtouch_p.h
index 7d909769d8a..93a829e2115 100644
--- a/src/plugins/platforms/wayland/qwaylandtouch_p.h
+++ b/src/plugins/platforms/wayland/qwaylandtouch_p.h
@@ -73,7 +73,7 @@ public:
 private:
     void registerDevice(int caps);
 
-    QWaylandDisplay *mDisplay;
+    QWaylandDisplay *mDisplay = nullptr;
 
     void touch_extension_touch(uint32_t time,
                                uint32_t id,
@@ -95,15 +95,15 @@ private:
 
     QList<QWindowSystemInterface::TouchPoint> mTouchPoints;
     QList<QWindowSystemInterface::TouchPoint> mPrevTouchPoints;
-    QTouchDevice *mTouchDevice;
+    QTouchDevice *mTouchDevice = nullptr;
     uint32_t mTimestamp;
     int mPointsLeft;
     uint32_t mFlags;
     int mMouseSourceId;
     QPointF mLastMouseLocal;
     QPointF mLastMouseGlobal;
-    QWindow *mTargetWindow;
-    QWaylandInputDevice *mInputDevice;
+    QWindow *mTargetWindow = nullptr;
+    QWaylandInputDevice *mInputDevice = nullptr;
 };
 
 }
diff --git a/src/plugins/platforms/wayland/qwaylandwindowmanagerintegration.cpp b/src/plugins/platforms/wayland/qwaylandwindowmanagerintegration.cpp
index 785a0a44d7c..17ae8a5ae85 100644
--- a/src/plugins/platforms/wayland/qwaylandwindowmanagerintegration.cpp
+++ b/src/plugins/platforms/wayland/qwaylandwindowmanagerintegration.cpp
@@ -61,7 +61,7 @@ class QWaylandWindowManagerIntegrationPrivate {
 public:
     QWaylandWindowManagerIntegrationPrivate(QWaylandDisplay *waylandDisplay);
     bool m_blockPropertyUpdates = false;
-    QWaylandDisplay *m_waylandDisplay;
+    QWaylandDisplay *m_waylandDisplay = nullptr;
     QHash<QWindow*, QVariantMap> m_queuedProperties;
     bool m_showIsFullScreen = false;
 };
diff --git a/src/plugins/platforms/wayland/qwaylandwlshellsurface_p.h b/src/plugins/platforms/wayland/qwaylandwlshellsurface_p.h
index 708c6f1132b..b0e677951cd 100644
--- a/src/plugins/platforms/wayland/qwaylandwlshellsurface_p.h
+++ b/src/plugins/platforms/wayland/qwaylandwlshellsurface_p.h
@@ -104,7 +104,7 @@ private:
     void updateTransientParent(QWindow *parent);
     void setPopup(QWaylandWindow *parent, QWaylandInputDevice *device, uint serial);
 
-    QWaylandWindow *m_window;
+    QWaylandWindow *m_window = nullptr;
     bool m_maximized = false;
     bool m_fullscreen = false;
     QSize m_size;
diff --git a/src/plugins/platforms/wayland/qwaylandxdgpopup_p.h b/src/plugins/platforms/wayland/qwaylandxdgpopup_p.h
index 85bd589bf7e..74c0dca2679 100644
--- a/src/plugins/platforms/wayland/qwaylandxdgpopup_p.h
+++ b/src/plugins/platforms/wayland/qwaylandxdgpopup_p.h
@@ -81,7 +81,7 @@ protected:
 
 private:
     QWaylandExtendedSurface *m_extendedWindow = nullptr;
-    QWaylandWindow *m_window;
+    QWaylandWindow *m_window = nullptr;
 };
 
 QT_END_NAMESPACE
diff --git a/src/plugins/platforms/wayland/qwaylandxdgshellv6_p.h b/src/plugins/platforms/wayland/qwaylandxdgshellv6_p.h
index 122beed0c8c..e59a67d69d8 100644
--- a/src/plugins/platforms/wayland/qwaylandxdgshellv6_p.h
+++ b/src/plugins/platforms/wayland/qwaylandxdgshellv6_p.h
@@ -106,7 +106,7 @@ private:
             QVarLengthArray<uint32_t> states;
         } m_configureState;
 
-        QWaylandXdgSurfaceV6 *m_xdgSurface;
+        QWaylandXdgSurfaceV6 *m_xdgSurface = nullptr;
     };
 
     class Popup : public QtWayland::zxdg_popup_v6 {
@@ -117,14 +117,14 @@ private:
         void applyConfigure();
         void zxdg_popup_v6_popup_done() override;
 
-        QWaylandXdgSurfaceV6 *m_xdgSurface;
+        QWaylandXdgSurfaceV6 *m_xdgSurface = nullptr;
     };
 
     void setToplevel();
     void setPopup(QWaylandWindow *parent, QWaylandInputDevice *device, int serial, bool grab);
 
-    QWaylandXdgShellV6 *m_shell;
-    QWaylandWindow *m_window;
+    QWaylandXdgShellV6 *m_shell = nullptr;
+    QWaylandWindow *m_window = nullptr;
     Toplevel *m_toplevel = nullptr;
     Popup *m_popup = nullptr;
     bool m_configured = false;
diff --git a/src/plugins/platforms/wayland/qwaylandxdgsurface_p.h b/src/plugins/platforms/wayland/qwaylandxdgsurface_p.h
index fa79632068a..42846c665fa 100644
--- a/src/plugins/platforms/wayland/qwaylandxdgsurface_p.h
+++ b/src/plugins/platforms/wayland/qwaylandxdgsurface_p.h
@@ -110,8 +110,8 @@ private:
     void updateTransientParent(QWaylandWindow *parent);
 
 private:
-    QWaylandWindow *m_window;
-    QWaylandXdgShell* m_shell;
+    QWaylandWindow *m_window = nullptr;
+    QWaylandXdgShell* m_shell = nullptr;
     bool m_maximized = false;
     bool m_minimized = false;
     bool m_fullscreen = false;
diff --git a/src/plugins/platforms/wayland/shared/qwaylandsharedmemoryformathelper_p.h b/src/plugins/platforms/wayland/shared/qwaylandsharedmemoryformathelper_p.h
index 7f2f77cc3c8..e5b5faf02e3 100644
--- a/src/plugins/platforms/wayland/shared/qwaylandsharedmemoryformathelper_p.h
+++ b/src/plugins/platforms/wayland/shared/qwaylandsharedmemoryformathelper_p.h
@@ -63,7 +63,7 @@ private:
             , data(data)
         { }
         const size_t size;
-        const wl_shm_format *data;
+        const wl_shm_format *data = nullptr;
     };
 
     static const Array getData()
diff --git a/src/plugins/platforms/wayland/shellintegration/qwaylandshellintegration_p.h b/src/plugins/platforms/wayland/shellintegration/qwaylandshellintegration_p.h
index ab9b736bbca..7f3a2cefcfd 100644
--- a/src/plugins/platforms/wayland/shellintegration/qwaylandshellintegration_p.h
+++ b/src/plugins/platforms/wayland/shellintegration/qwaylandshellintegration_p.h
@@ -81,7 +81,7 @@ public:
     }
 
 protected:
-    QWaylandDisplay *m_display;
+    QWaylandDisplay *m_display = nullptr;
 };
 
 }
diff --git a/tests/auto/wayland/client/tst_client.cpp b/tests/auto/wayland/client/tst_client.cpp
index 8ee52d7364f..4eb85818c76 100644
--- a/tests/auto/wayland/client/tst_client.cpp
+++ b/tests/auto/wayland/client/tst_client.cpp
@@ -170,7 +170,7 @@ private slots:
     void glWindow();
 
 private:
-    MockCompositor *compositor;
+    MockCompositor *compositor = nullptr;
 };
 
 void tst_WaylandClient::primaryScreen()
diff --git a/tests/auto/wayland/shared/mockcompositor.h b/tests/auto/wayland/shared/mockcompositor.h
index c6de12376a3..c0c3c884f34 100644
--- a/tests/auto/wayland/shared/mockcompositor.h
+++ b/tests/auto/wayland/shared/mockcompositor.h
@@ -141,7 +141,7 @@ private:
     friend class Impl::Compositor;
     friend class Impl::Surface;
 
-    Impl::Surface *m_surface;
+    Impl::Surface *m_surface = nullptr;
 };
 
 Q_DECLARE_METATYPE(QSharedPointer<MockSurface>)
@@ -151,7 +151,7 @@ public:
     Impl::Output *handle() const { return m_output; }
     MockOutput(Impl::Output *output);
 private:
-    Impl::Output *m_output;
+    Impl::Output *m_output = nullptr;
 };
 
 Q_DECLARE_METATYPE(QSharedPointer<MockOutput>)
@@ -201,7 +201,7 @@ private:
         typedef void (*Callback)(void *target, const QList<QVariant> &parameters);
 
         Callback callback;
-        void *target;
+        void *target = nullptr;
         QList<QVariant> parameters;
     };
 
diff --git a/tests/auto/wayland/shared/mockinput.h b/tests/auto/wayland/shared/mockinput.h
index 5760ab40c63..d9adb3621f2 100644
--- a/tests/auto/wayland/shared/mockinput.h
+++ b/tests/auto/wayland/shared/mockinput.h
@@ -60,7 +60,7 @@ protected:
     void seat_get_touch(Resource *resource, uint32_t id) override;
 
 private:
-    Compositor *m_compositor;
+    Compositor *m_compositor = nullptr;
 
     QScopedPointer<Keyboard> m_keyboard;
     QScopedPointer<Pointer> m_pointer;
@@ -83,7 +83,7 @@ protected:
     void keyboard_destroy_resource(wl_keyboard::Resource *resource) override;
 
 private:
-    Compositor *m_compositor;
+    Compositor *m_compositor = nullptr;
 
     Resource *m_focusResource = nullptr;
     Surface *m_focus = nullptr;
@@ -106,7 +106,7 @@ protected:
     void pointer_destroy_resource(wl_pointer::Resource *resource) override;
 
 private:
-    Compositor *m_compositor;
+    Compositor *m_compositor = nullptr;
 
     Resource *m_focusResource = nullptr;
     Surface *m_focus = nullptr;
@@ -121,7 +121,7 @@ public:
     void sendMotion(Surface *surface, const QPoint &position, int id);
     void sendFrame(Surface *surface);
 private:
-    Compositor *m_compositor;
+    Compositor *m_compositor = nullptr;
 };
 
 class DataOffer : public QtWaylandServer::wl_data_offer
@@ -145,7 +145,7 @@ protected:
     void data_device_start_drag(Resource *resource, struct ::wl_resource *source, struct ::wl_resource *origin, struct ::wl_resource *icon, uint32_t serial) override;
 
 private:
-    Compositor *m_compositor;
+    Compositor *m_compositor = nullptr;
     QtWaylandServer::wl_data_offer *m_dataOffer = nullptr;
     Surface* m_focus = nullptr;
 };
@@ -162,7 +162,7 @@ protected:
     void data_device_manager_create_data_source(Resource *resource, uint32_t id) override;
 
 private:
-    Compositor *m_compositor;
+    Compositor *m_compositor = nullptr;
 
     QScopedPointer<DataDevice> m_data_device;
 };
diff --git a/tests/auto/wayland/shared/mocksurface.h b/tests/auto/wayland/shared/mocksurface.h
index 8bf6eb755a2..68fe9b94ce4 100644
--- a/tests/auto/wayland/shared/mocksurface.h
+++ b/tests/auto/wayland/shared/mocksurface.h
@@ -65,7 +65,7 @@ protected:
 private:
     wl_resource *m_buffer = nullptr;
 
-    Compositor *m_compositor;
+    Compositor *m_compositor = nullptr;
     QSharedPointer<MockSurface> m_mockSurface;
     QList<wl_resource *> m_frameCallbackList;
     bool m_mapped = false;
diff --git a/tests/auto/wayland/xdgshellv6/tst_xdgshellv6.cpp b/tests/auto/wayland/xdgshellv6/tst_xdgshellv6.cpp
index 5aac336f272..9e4aa8c07a1 100644
--- a/tests/auto/wayland/xdgshellv6/tst_xdgshellv6.cpp
+++ b/tests/auto/wayland/xdgshellv6/tst_xdgshellv6.cpp
@@ -82,7 +82,7 @@ private slots:
     void createDestroyWindow();
 
 private:
-    MockCompositor *m_compositor;
+    MockCompositor *m_compositor = nullptr;
 };
 
 void tst_WaylandClientXdgShellV6::createDestroyWindow()