QObject: Q_ASSERT the object type before calling a PMF

The old-syle signal-slot syntax had the advantage of not delivering
signals to slots in derived classes after that derived class's
destructor had finished running (because we called via the virtual
qt_metacall). The new syntax made no checks, so a conversion from the
old to the new syntax may introduce crashes or other data corruptions at
runtime if the destructor had completed.

This commit introduces a Q_ASSERT to print the class name that the
object is not any more. Since this is in inline code, this should get
enabled for users' debug modes and does not therefore depend on Qt being
built in debug mode.

It required some Private classes to be adapted to the new form, by
exposing the public q_func() in the public: part.

Pick-to: 6.2
Fixes: QTBUG-33908
Change-Id: Iccb47e5527544b6fbd75fffd16b874cdc08c1f3e
Reviewed-by: Marc Mutz <marc.mutz@qt.io>
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Giuseppe D'Angelo <giuseppe.dangelo@kdab.com>

0 files changed, 0 insertions, 0 deletions