QQmlDelegateModel: Fix QQmlDelegateModelItem::dataForObject

With required properties, we do not store the cache item as a context
object anymore. To fix this, we repurpose the (space of the) incubator
pointer of QQmlContextData to store the element there, and one of the
dummy bits as a flag to indicate the new usage.

Change-Id: I7cc435fc6781c603fe407411a60a6018239c972c
Reviewed-by: Ulf Hermann <ulf.hermann@qt.io>

1 files changed, 8 insertions, 3 deletions

diff --git a/src/qml/qml/qqmlcontext_p.h b/src/qml/qml/qqmlcontext_p.h
index 5f7316b00c..f93393a11b 100644
--- a/src/qml/qml/qqmlcontext_p.h
+++ b/src/qml/qml/qqmlcontext_p.h
@@ -147,11 +147,16 @@ public:
     quint32 hasEmittedDestruction:1;
     quint32 isRootObjectInCreation:1;
     quint32 stronglyReferencedByParent:1;
-    quint32 dummy:25;
+    quint32 hasExtraObject:1; // used in QQmlDelegateModelItem::dataForObject to find the corresponding QQmlDelegateModelItem of an object
+    quint32 dummy:24;
     QQmlContext *publicContext;
 
-    // The incubator that is constructing this context if any
-    QQmlIncubatorPrivate *incubator;
+    union {
+        // The incubator that is constructing this context if any
+        QQmlIncubatorPrivate *incubator;
+        // a pointer to extra data, currently only used in QQmlDelegateModel
+        QObject *extraObject;
+    };
 
     // Compilation unit for contexts that belong to a compiled type.
     QQmlRefPointer<QV4::ExecutableCompilationUnit> typeCompilationUnit;