Fix crash in QObjectWrapper

This can happen during QObject destruction, when
QObjectPrivate::deleteChildren() itself sets entries
in the children list to zero when deleting. These
zeros cause crash in markChildQObjectsRecursively().

Task-number: QTBUG-38635
Change-Id: I29ad9e793b78ca4e8d73fbb125f46db1b8292f20
Reviewed-by: Alan Alpert <[email protected]>

1 files changed, 2 insertions, 0 deletions

diff --git a/src/qml/jsruntime/qv4qobjectwrapper.cpp b/src/qml/jsruntime/qv4qobjectwrapper.cpp
index a02424a3dc..d64f821a38 100644
--- a/src/qml/jsruntime/qv4qobjectwrapper.cpp
+++ b/src/qml/jsruntime/qv4qobjectwrapper.cpp
@@ -962,6 +962,8 @@ static void markChildQObjectsRecursively(QObject *parent, QV4::ExecutionEngine *
     const QObjectList &children = parent->children();
     for (int i = 0; i < children.count(); ++i) {
         QObject *child = children.at(i);
+        if (!child)
+            continue;
         QQmlData *ddata = QQmlData::get(child, /*create*/false);
         if (ddata)
             ddata->jsWrapper.markOnce(e);