ctkPluginFrameworkPrivate: crash on deactivate

[Cynede]

on application close in shutdown0 with wasActive flag in deactivate(this->pluginContext.data()); I'm getting SIGSEGV (on Linux)

call stack points on

bool ctkPluginContext::ungetService(const ctkServiceReference& reference)
{
  Q_D(ctkPluginContext);
  d->isPluginContextValid();
  ctkServiceReference ref = reference;
  return ref.d_func()->ungetService(d->plugin->q_func(), true); // <-- this
}

inside some weak pointer access there on closing some system service