Calling anonymous function from a pointer

I get an access violation while trying to call an anonymous method from a Pointer variable

var
  Proc : TProc;
  Pt : Pointer;
begin
  Proc := procedure
  begin
    ShowMessage('Hello World');
  end;

  Pt := @Proc;
  TProc(Pt)();
end;

In debug I see that Pt is evalued