Merge remote-tracking branch 'origin/5.14' into 5.15

Change-Id: Idf4c63d08423691afd8823c734ba79085aa9e14f

2 files changed, 8 insertions, 3 deletions

diff --git a/src/client/qwaylanddisplay.cpp b/src/client/qwaylanddisplay.cpp
index a17e8917a..0464d3a42 100644
--- a/src/client/qwaylanddisplay.cpp
+++ b/src/client/qwaylanddisplay.cpp
@@ -114,6 +114,10 @@ struct ::wl_region *QWaylandDisplay::createRegion(const QRegion &qregion)
         return nullptr;
     }
 
+    // Make sure we don't pass NULL surfaces to libwayland (crashes)
+    Q_ASSERT(parent->wlSurface());
+    Q_ASSERT(window->wlSurface());
+
     return mSubCompositor->get_subsurface(window->wlSurface(), parent->wlSurface());
 }
 
diff --git a/src/client/qwaylandwindow.cpp b/src/client/qwaylandwindow.cpp
index bffb57015..950486c0c 100644
--- a/src/client/qwaylandwindow.cpp
+++ b/src/client/qwaylandwindow.cpp
@@ -125,9 +125,10 @@ void QWaylandWindow::initWindow()
     if (shouldCreateSubSurface()) {
         Q_ASSERT(!mSubSurfaceWindow);
 
-        QWaylandWindow *p = static_cast<QWaylandWindow *>(QPlatformWindow::parent());
-        if (::wl_subsurface *ss = mDisplay->createSubSurface(this, p)) {
-            mSubSurfaceWindow = new QWaylandSubSurface(this, p, ss);
+        auto *parent = static_cast<QWaylandWindow *>(QPlatformWindow::parent());
+        if (parent->wlSurface()) {
+            if (::wl_subsurface *subsurface = mDisplay->createSubSurface(this, parent))
+                mSubSurfaceWindow = new QWaylandSubSurface(this, parent, subsurface);
         }
     } else if (shouldCreateShellSurface()) {
         Q_ASSERT(!mShellSurface);