Memory leak in QHeaderView attached to QTreeView with hidden sections

The sequence

• Create QTreeView
• Create Model
• Call setModel()
• Put some rows in the Model
• Call setColumnHidden
• Trigger the model's about-to-change-layout signal and change-layout signal

leaks memory in the QHeaderView by filling up a QList and never emptying it. QHeaderViewPrivate::persistentHiddenSections is appended to in QHeaderView::_q_layoutAboutToBeChanged(), and cleared in _q_layoutChanged(), but QTreeView::setModel() disconnects the layoutChanged() signal to its QHeaderView, and doesn't seem to pass it down via any other mechanism. As a result, the list grows by a few elements every time the model goes through layout-change processing.

Calling QTreeView::setHeader() after setModel results in a QTreeView that does not have this problem - only setModel() disconnects the signal, not setHeader().

I have verified the problem in Qt 4.6.2 and 4.7.3