6 files changed, 102 insertions, 10 deletions

diff --git a/src/corelib/tools/qhash.h b/src/corelib/tools/qhash.h
index 0777f06..c7e4bc1 100644
--- a/src/corelib/tools/qhash.h
+++ b/src/corelib/tools/qhash.h
@@ -589,10 +589,11 @@ template <class Key, class T>
 Q_INLINE_TEMPLATE QHash<Key, T> &QHash<Key, T>::operator=(const QHash<Key, T> &other)
 {
     if (d != other.d) {
-        other.d->ref.ref();
+        QHashData *o = other.d;
+        o->ref.ref();
         if (!d->ref.deref())
             freeData(d);
-        d = other.d;
+        d = o;
         if (!d->sharable)
             detach_helper();
     }
diff --git a/src/corelib/tools/qlinkedlist.h b/src/corelib/tools/qlinkedlist.h
index d145fe3..9b3efa3 100644
--- a/src/corelib/tools/qlinkedlist.h
+++ b/src/corelib/tools/qlinkedlist.h
@@ -312,10 +312,11 @@ template <typename T>
 QLinkedList<T> &QLinkedList<T>::operator=(const QLinkedList<T> &l)
 {
     if (d != l.d) {
-        l.d->ref.ref();
+        QLinkedListData *o = l.d;
+        o->ref.ref();
         if (!d->ref.deref())
             free(d);
-        d = l.d;
+        d = o;
         if (!d->sharable)
             detach_helper();
     }
diff --git a/src/corelib/tools/qlist.h b/src/corelib/tools/qlist.h
index 722744c..d843cbe 100644
--- a/src/corelib/tools/qlist.h
+++ b/src/corelib/tools/qlist.h
@@ -424,10 +424,11 @@ template <typename T>
 Q_INLINE_TEMPLATE QList<T> &QList<T>::operator=(const QList<T> &l)
 {
     if (d != l.d) {
-        l.d->ref.ref();
+        QListData::Data *o = l.d;
+        o->ref.ref();
         if (!d->ref.deref())
             free(d);
-        d = l.d;
+        d = o;
         if (!d->sharable)
             detach_helper();
     }
diff --git a/src/corelib/tools/qmap.h b/src/corelib/tools/qmap.h
index e4b73a1..1c2aad3 100644
--- a/src/corelib/tools/qmap.h
+++ b/src/corelib/tools/qmap.h
@@ -426,10 +426,11 @@ template <class Key, class T>
 Q_INLINE_TEMPLATE QMap<Key, T> &QMap<Key, T>::operator=(const QMap<Key, T> &other)
 {
     if (d != other.d) {
-        other.d->ref.ref();
+        QMapData* o = other.d;
+        o->ref.ref();
         if (!d->ref.deref())
             freeData(d);
-        d = other.d;
+        d = o;
         if (!d->sharable)
             detach_helper();
     }
diff --git a/src/corelib/tools/qvector.h b/src/corelib/tools/qvector.h
index c2e2485..b762b8a 100644
--- a/src/corelib/tools/qvector.h
+++ b/src/corelib/tools/qvector.h
@@ -377,10 +377,11 @@ inline void QVector<T>::replace(int i, const T &t)
 template <typename T>
 QVector<T> &QVector<T>::operator=(const QVector<T> &v)
 {
-    v.d->ref.ref();
+    QVectorData *o = v.d;
+    o->ref.ref();
     if (!d->ref.deref())
         free(p);
-    d = v.d;
+    d = o;
     if (!d->sharable)
         detach_helper();
     return *this;
diff --git a/tests/auto/collections/tst_collections.cpp b/tests/auto/collections/tst_collections.cpp
index d092c34..8617e02 100644
--- a/tests/auto/collections/tst_collections.cpp
+++ b/tests/auto/collections/tst_collections.cpp
@@ -165,6 +165,7 @@ private slots:
     void containerTypedefs();
     void forwardDeclared();
     void alignment();
+    void QTBUG13079_collectionInsideCollection();
 };
 
 struct LargeStatic {
@@ -3589,5 +3590,91 @@ void tst_Collections::alignment()
 }
 #endif
 
+#ifndef QT_NO_TEMPLATE_TEMPLATE_PARAMETERS
+
+template<template<class> class C>
+struct QTBUG13079_Node {
+    C<QTBUG13079_Node> children;
+    QString s;
+
+    ~QTBUG13079_Node() {
+        children.begin(); //play with memory
+    }
+};
+template<template<class> class C> void QTBUG13079_collectionInsideCollectionImpl()
+{
+    C<QTBUG13079_Node<C> > nodeList;
+    nodeList << QTBUG13079_Node<C>();
+    nodeList.first().s = "parent";
+    nodeList.first().children << QTBUG13079_Node<C>();
+    nodeList.first().children.first().s = "child";
+
+    nodeList = nodeList.first().children;
+    QCOMPARE(nodeList.first().s, QString::fromLatin1("child"));
+
+    nodeList = nodeList.first().children;
+    QCOMPARE(nodeList.count(), 0);
+    nodeList << QTBUG13079_Node<C>();
+}
+
+template<template<class, class> class C>
+struct QTBUG13079_NodeAssoc {
+    C<int, QTBUG13079_NodeAssoc> children;
+    QString s;
+
+    ~QTBUG13079_NodeAssoc() {
+        children.begin(); //play with memory
+    }
+};
+template<template<class, class> class C> void QTBUG13079_collectionInsideCollectionAssocImpl()
+{
+    C<int, QTBUG13079_NodeAssoc<C> > nodeMap;
+    nodeMap[18] = QTBUG13079_NodeAssoc<C>();
+    nodeMap[18].s = "parent";
+    nodeMap[18].children[12] = QTBUG13079_NodeAssoc<C>();
+    nodeMap[18].children[12].s = "child";
+
+    nodeMap = nodeMap[18].children;
+    QCOMPARE(nodeMap[12].s, QString::fromLatin1("child"));
+
+    nodeMap = nodeMap[12].children;
+    QCOMPARE(nodeMap.count(), 0);
+    nodeMap[42] = QTBUG13079_NodeAssoc<C>();
+}
+
+
+static quint32 qHash(const QTBUG13079_Node<QSet> &)
+{
+    return 0;
+}
+
+bool operator==(const QTBUG13079_Node<QSet> &a, const QTBUG13079_Node<QSet> &b)
+{
+    return a.s == b.s && a.children == b.children;
+}
+
+#endif
+
+void tst_Collections::QTBUG13079_collectionInsideCollection()
+{
+#ifndef QT_NO_TEMPLATE_TEMPLATE_PARAMETERS
+    QTBUG13079_collectionInsideCollectionImpl<QVector>();
+    QTBUG13079_collectionInsideCollectionImpl<QStack>();
+    QTBUG13079_collectionInsideCollectionImpl<QList>();
+    QTBUG13079_collectionInsideCollectionImpl<QLinkedList>();
+    QTBUG13079_collectionInsideCollectionImpl<QQueue>();
+
+    {
+        QSet<QTBUG13079_Node<QSet> > nodeSet;
+        nodeSet << QTBUG13079_Node<QSet>();
+        nodeSet = nodeSet.begin()->children;
+        QCOMPARE(nodeSet.count(), 0);
+    }
+
+    QTBUG13079_collectionInsideCollectionAssocImpl<QMap>();
+    QTBUG13079_collectionInsideCollectionAssocImpl<QHash>();
+#endif
+}
+
 QTEST_APPLESS_MAIN(tst_Collections)
 #include "tst_collections.moc"