Autotest: make sure we can't create QWeakPointer from a QObject in destruction.

This test only works in debug mode

2 files changed, 17 insertions, 0 deletions

diff --git a/src/corelib/tools/qsharedpointer.cpp b/src/corelib/tools/qsharedpointer.cpp
index f793f26..e3e1db6 100644
--- a/src/corelib/tools/qsharedpointer.cpp
+++ b/src/corelib/tools/qsharedpointer.cpp
@@ -977,6 +977,8 @@ QtSharedPointer::ExternalRefCountData *QtSharedPointer::ExternalRefCountData::ge
 {
     Q_ASSERT(obj);
     QObjectPrivate *d = QObjectPrivate::get(const_cast<QObject *>(obj));
+    Q_ASSERT_X(!d->wasDeleted, "QWeakPointer", "Detected QWeakPointer creation in a QObject being deleted");
+
     ExternalRefCountData *that = d->sharedRefcount;
     if (that) {
         that->weakref.ref();
diff --git a/tests/auto/qsharedpointer/tst_qsharedpointer.cpp b/tests/auto/qsharedpointer/tst_qsharedpointer.cpp
index 6bc3aa0..58e5401 100644
--- a/tests/auto/qsharedpointer/tst_qsharedpointer.cpp
+++ b/tests/auto/qsharedpointer/tst_qsharedpointer.cpp
@@ -1593,6 +1593,21 @@ void tst_QSharedPointer::invalidConstructs_data()
         << "QObject *ptr = new QObject;\n"
            "QWeakPointer<QObject> weak = ptr;\n"    // this makes the object unmanaged
            "QSharedPointer<QObject> shared(ptr);\n";
+
+#ifndef QT_NO_DEBUG
+    // this tests a Q_ASSERT, so it is only valid in debug mode
+    // the DerivedFromQObject destructor below creates a QWeakPointer from parent().
+    // parent() is not 0 in the current Qt implementation, but has started destruction,
+    // so the code should detect that issue
+    QTest::newRow("shared-pointer-from-qobject-in-destruction")
+        << &QTest::QExternalTest::tryRunFail
+        << "class DerivedFromQObject: public QObject { public:\n"
+           "    DerivedFromQObject(QObject *parent): QObject(parent) {}\n"
+           "    ~DerivedFromQObject() { QWeakPointer<QObject> weak = parent(); }\n"
+           "};\n"
+           "QObject obj;\n"
+           "new DerivedFromQObject(&obj);";
+#endif
 }
 
 void tst_QSharedPointer::invalidConstructs()