Protect unregisterInternalCompositeType() against null metatype data

This may be called on shutdown when the data is already gone.

Fixes: QDS-4390
Change-Id: I89de5fc1e66fca4318939179ed356620110b08e9
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>
Reviewed-by: Andrei Golubev <andrei.golubev@qt.io>
Reviewed-by: Thomas Hartmann <thomas.hartmann@qt.io>
(cherry picked from commit 98af4ab983b9b33c6f5cdb71f6f4f4dd7419aa30)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>

1 files changed, 7 insertions, 5 deletions

diff --git a/src/qml/qml/qqmlmetatype.cpp b/src/qml/qml/qqmlmetatype.cpp
index 8b92a2ff8c..a8cd22e353 100644
--- a/src/qml/qml/qqmlmetatype.cpp
+++ b/src/qml/qml/qqmlmetatype.cpp
@@ -588,12 +588,14 @@ void QQmlMetaType::unregisterInternalCompositeType(const CompositeMetaTypeIds &t
     QMetaType metaType(typeIds.id);
     QMetaType listMetaType(typeIds.listId);
 
+    // This may be called from delayed dtors on shutdown when the data is already gone.
     QQmlMetaTypeDataPtr data;
-
-    if (QQmlValueType *vt = data->metaTypeToValueType.take(metaType.id()))
-        delete vt;
-    if (QQmlValueType *vt = data->metaTypeToValueType.take(listMetaType.id()))
-        delete vt;
+    if (data.isValid()) {
+        if (QQmlValueType *vt = data->metaTypeToValueType.take(metaType.id()))
+            delete vt;
+        if (QQmlValueType *vt = data->metaTypeToValueType.take(listMetaType.id()))
+            delete vt;
+    }
 
     QMetaType::unregisterMetaType(metaType);
     QMetaType::unregisterMetaType(listMetaType);