PVS-Studio warning V529 for ReactOS

BOOLEAN
CTEScheduleEvent(PCTE_DELAYED_EVENT Event,
                 PVOID Context)
{
  ...
  if (!Event->Queued);
  {
    Event->Queued = TRUE;
    Event->Context = Context;
    ExQueueWorkItem(&Event->WorkItem, CriticalWorkQueue);
  }
  ...
}

This suspicious code was found in ReactOS project by PVS-Studio static code analyzer.
Warning message is:
V529 Odd semicolon ';' after 'if' operator. tdi events.c 126

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