QQmlMetaObjectPointer: restrict copy ctor to QQmlPropertyCache

... using friendship.

Pick-to: 6.3
Change-Id: I311256d7e8d167120e31142b846615d793e17ce1
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>
Reviewed-by: Ulf Hermann <ulf.hermann@qt.io>

1 files changed, 4 insertions, 0 deletions

diff --git a/src/qml/qml/qqmlpropertycache_p.h b/src/qml/qml/qqmlpropertycache_p.h
index e6a08f33c7..8177e72821 100644
--- a/src/qml/qml/qqmlpropertycache_p.h
+++ b/src/qml/qml/qqmlpropertycache_p.h
@@ -69,6 +69,7 @@ class QCryptographicHash;
 class QJSEngine;
 class QMetaObjectBuilder;
 class QQmlContextData;
+class QQmlPropertyCache;
 class QQmlPropertyCacheMethodArguments;
 class QQmlVMEMetaObject;
 
@@ -90,6 +91,8 @@ public:
             reinterpret_cast<SharedHolder *>(dd ^ Shared)->release();
     }
 
+private:
+    friend class QQmlPropertyCache;
     QQmlMetaObjectPointer(const QQmlMetaObjectPointer &other)
         : d(other.d.loadRelaxed())
     {
@@ -103,6 +106,7 @@ public:
     QQmlMetaObjectPointer &operator=(QQmlMetaObjectPointer &&other) = delete;
     QQmlMetaObjectPointer &operator=(const QQmlMetaObjectPointer &other) = delete;
 
+public:
     void setSharedOnce(QMetaObject *shared) const
     {
         SharedHolder *holder = new SharedHolder(shared);