From c8a4894655eef230702e6cc889f3d40fbb5a9426 Mon Sep 17 00:00:00 2001

From: Ulf Hermann <ulf.hermann@qt.io>

Date: Thu, 3 Feb 2022 10:02:06 +0100

Subject: [PATCH 19/20] V4: Do not call dtor of an object we continue to use

After destroyObject(), the QObjectWrapper is still alive. We might use

its heap object again. Furthermore, the Heap::QObjectWrapper dtor does

not actually do anything defined. What we want to do here is clear the

QObject pointer because we've just gotten rid of the QObject. There is a

method for that: Heap::QObjectWrapper::destroy().

Finally, the internalClass must never ever be nullptr. Assert on that

rather than checking it.

Pick-to: 5.15 6.2 6.3

Task-number: QTBUG-100431

Change-Id: I794a295c182b2ed4ba80673f58d6143c861b7391

Reviewed-by: Andrei Golubev <andrei.golubev@qt.io>

Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>

Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>

(cherry picked from commit 6c197319f34b8098d034f1543eb5feb9d7be54c3)

---

 src/qml/jsruntime/qv4qobjectwrapper.cpp | 5 ++---

 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/src/qml/jsruntime/qv4qobjectwrapper.cpp b/src/qml/jsruntime/qv4qobjectwrapper.cpp

index 9899c9274e..272b85069f 100644

--- a/src/qml/jsruntime/qv4qobjectwrapper.cpp

+++ b/src/qml/jsruntime/qv4qobjectwrapper.cpp

@@ -1160,8 +1160,7 @@ void Heap::QObjectWrapper::markObjects(Heap::Base *that, QV4::MarkStack *markSta

 void QObjectWrapper::destroyObject(bool lastCall)

 {

     Heap::QObjectWrapper *h = d();

-    if (!h->internalClass)

-        return; // destroyObject already got called

+    Q_ASSERT(h->internalClass);

     if (h->object()) {

         QQmlData *ddata = QQmlData::get(h->object(), false);

@@ -1191,7 +1190,7 @@ void QObjectWrapper::destroyObject(bool lastCall)

         }

     }

-    h->~Data();

+    h->destroy();

 }

-- 

2.35.1