Delphi Error – E2080 Procedure DISPOSE needs destructor

Delphi Compiler Error

E2080 Procedure DISPOSE needs destructor

Reason for the Error & Solution

This error message is issued when an identifier given in the parameter list to Dispose is not a destructor.

program Produce;

type
  PMyObject = ^TMyObject;
  TMyObject = object
  F: Integer;
  constructor Init;
  destructor Done;
  end;

constructor TMyObject.Init;
begin
  F := 42;
end;

destructor TMyObject.Done;
begin
end;

var
  P: PMyObject;

begin
  New(P, Init);
  (*...*)
  Dispose(P, Init);        (*<-- Error message here*)
end.

In this example, we passed the constructor to Dispose by mistake.

program Solve;

type
  PMyObject = ^TMyObject;
  TMyObject = object
  F: Integer;
  constructor Init;
  destructor Done;
  end;

constructor TMyObject.Init;
begin
  F := 42;
end;

destructor TMyObject.Done;
begin
end;

var
  P: PMyObject;

begin
  New(P, Init);
  Dispose(P, Done);
end.

The solution is to either pass a destructor to Dispose, or to eliminate the second argument.