TTest = packed record

a: Integer;

case Byte of

0: (b1: Integer);

1: (b2: TPoint);

end;


procedure TForm1.Button1Click(Sender: TObject);
var
La: TTest;
begin
La.a := 0;
La.b1 := 1;
La.b2.X := 2;

ShowMessage(Format('Size=%d; b1=%d', [SizeOf(La), La.b1]));
end;