Examples of errors detected by the V757 diagnostic

V757. It is possible that an incorrect variable is compared with null after type conversion using 'dynamic_cast'.

LibreOffice

V757 It is possible that an incorrect variable is compared with nullptr after type conversion using 'dynamic_cast'. Check lines: 2709, 2710. menu.cxx 2709


void PopupMenu::ClosePopup(Menu* pMenu)
{
  MenuFloatingWindow* p = dynamic_cast<MenuFloatingWindow*>(ImplGetWindow());
  PopupMenu *pPopup = dynamic_cast<PopupMenu*>(pMenu);
  if (p && pMenu)
    p->KillActivePopup(pPopup);
}

Haiku Operation System

V757 It is possible that an incorrect variable is compared with nullptr after type conversion using 'dynamic_cast'. Check lines: 474, 476. recover.cpp 474


void
checkStructure(Disk &disk)
{
  ....
  Inode* missing = gMissing.Get(run);
  dir = dynamic_cast<Directory *>(missing);

  if (missing == NULL) {
    ....
  }
  ....
}

Similar errors can be found in some other places:

V757 It is possible that an incorrect variable is compared with nullptr after type conversion using 'dynamic_cast'. Check lines: 355, 357. ExpandoMenuBar.cpp 355
V757 It is possible that an incorrect variable is compared with nullptr after type conversion using 'dynamic_cast'. Check lines: 600, 601. ValControl.cpp 600