First chance exception at $008E331C. Exception class $C0000005

First chance exception at $008E331C. Exception class $C0000005 with message 'access violation at 0x008e331c:

read of address 0x00000008'. Process KSQL.exe (18380)

d:\program files (x86)\embarcadero\studio\21.0\source\rtl\common\System.Classes.pas

class procedure TLinkObserversHelper.IteratorLinkUpdateControlComponent(const AObservers: TObservers; AControl: TComponent);
var
  LList: IInterfaceList;
  LIteratorLinkObserver: IIteratorLinkObserver;
  I: Integer;
begin
  LList := AObservers.GetMultiCastObserver(TObserverMapping.IteratorLinkID);
  for I := 0 to LList.Count - 1 do
  begin
    if Supports(LList[I], IIteratorLinkObserver, LIteratorLinkObserver) then
      LIteratorLinkObserver.UpdateControlComponent(AControl);
  end;
end;

First chance exception at $006C1074. Exception class $C0000005 with message 'access violation at 0x006c1074: read of address 0x00000008'. Process KSQL2.exe (16104)

System.Generics.Collections.pas

function TThreadList<T>.LockList: TList<T>;
begin
  TMonitor.Enter(FLock);
  Result := FList;
end;

沒辦法，工程重建好了

最后發現是cb的功能里添加了dpubunit.pas文件，移除就好了.