Delphi – E2027 Duplicate tag value

When a constant appears in the declaration of a variant record more than once, this error notice displays.

program Produce;
type
  VariantRecord = record
    case Integer of
    0  (IntField: Integer);
    0  (RealField: Real);     (*<-- Error message here*)
  end;

begin
end.
	program Solve;
type
  VariantRecord = record
    case Integer of
    0  (IntField: Integer);
    1 (RealField: Real);
  end;

begin
end.