program Project41;

uses
  FastMM4,
  System.SysUtils;

{$APPTYPE CONSOLE}

{$R *.res}

type TObj = class
  strict private
    FPayload2: string;
    FPayload1: double;
    procedure SetPayload1(const Value: double);
    procedure SetPayload2(const Value: string);
  public
    property Payload1: double read FPayload1 write SetPayload1;
    property Payload2: string read FPayload2 write SetPayload2;
end;

{ TObj }

procedure TObj.SetPayload1(const Value: double);
begin
  FPayload1 := Value;
end;

procedure TObj.SetPayload2(const Value: string);
begin
  FPayload2 := Value;
end;

var o: TObj;

procedure Dump(const o: TObj);
begin
  Writeln ( o.Payload1 :20 :10, ' - ', o.Payload2 );
end;

begin
  try
    o := TObj.Create;
    o.Payload2 := 'ABCDF';
    o.Payload1 := Pi;

    Dump(o);
    o.Destroy;
    Dump(o);
  except
    on E: Exception do
      Writeln(E.Message);
  end;
  Readln;
end.

program Project41;

uses
  FastMM4,

............

begin
  try
    o := TObj.Create;
    o.Payload2 := 'ABCDF';
    o.Payload1 := Pi;

    Dump(o);
    o.Destroy;
    o.Destroy;
    Dump(o);
  except
    on E: Exception do
      Writeln(E.Message);
  end;
  Readln;
end.

--------------------------------2019/3/29 15:33:08--------------------------------
FastMM has detected an attempt to call a virtual method on a freed object. An access violation will now be raised in order to abort the current operation.

Freed object class: TObj

Virtual method: Destroy

Virtual method address: 405D9C

The allocation number was: 109

The object was allocated by thread 0x1890, and the stack trace (return addresses) at the time was:
403DEA 
405D53 
40634E 
405D88 
4223FD 
772B86E3 [BaseThreadInitThunk]
7752BD99 [Unknown function at RtlInitializeExceptionChain]
7752BD6C [Unknown function at RtlInitializeExceptionChain]

The object was subsequently freed by thread 0x1890, and the stack trace (return addresses) at the time was:
403E06 
405D71 
406399 
405DAA 
42243B 
772B86E3 [BaseThreadInitThunk]
7752BD99 [Unknown function at RtlInitializeExceptionChain]
7752BD6C [Unknown function at RtlInitializeExceptionChain]

The current thread ID is 0x1890, and the stack trace (return addresses) leading to this error is:
422447 
772B86E3 [BaseThreadInitThunk]
7752BD99 [Unknown function at RtlInitializeExceptionChain]
7752BD6C [Unknown function at RtlInitializeExceptionChain]

Current memory dump of 256 bytes starting at pointer address 7FE8CCD0:
7C B2 42 00 70 B5 42 00 70 B5 42 00 70 B5 42 00 70 B5 42 00 A1 05 AC B1 00 00 00 00 91 CD E8 7F
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 76 00 00 00 EA 3D 40 00 6F 70 40 00 58 72 40 00
2F 73 40 00 50 25 52 77 B6 55 52 77 61 88 55 77 40 C2 4F 77 EE 56 52 77 EE 56 52 77 9D 53 52 77
90 18 00 00 90 18 00 00 06 3E 40 00 11 71 40 00 57 50 40 00 84 51 40 00 B4 54 40 00 E2 F8 41 00
2F 24 42 00 E3 86 2B 77 99 BD 52 77 6C BD 52 77 00 00 00 00 10 00 00 00 B0 04 02 00 E5 22 C4 2B
7C B2 42 00 70 B5 42 00 70 B5 42 00 70 B5 42 00 1A DD 3B D4 70 B5 42 00 00 00 00 00 31 CE E8 7F
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 77 00 00 00 B0 70 40 00 63 77 40 00 C8 73 40 00
12 54 40 00 6B 53 40 00 28 50 40 00 84 51 40 00 B4 54 40 00 E2 F8 41 00 2F 24 42 00 E3 86 2B 77
|  І  B  .  p  µ  B  .  p  µ  B  .  p  µ  B  .  p  µ  B  .  Ў  .  ¬  ±  .  .  .  .  ‘  Н  и  
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--------------------------------2019/3/29 15:34:09--------------------------------
FastMM has detected an attempt to call a virtual method on a freed object. An access violation will now be raised in order to abort the current operation.

Freed object class: TObj

Virtual method: Destroy

Virtual method address: 405D9C

The allocation number was: 109

The object was allocated by thread 0xA34, and the stack trace (return addresses) at the time was:
403DEA 
405D53 
40634E 
405D88 
4223FD [Project41.dpr][Project41][Project41.Project41][43]
772B86E3 [BaseThreadInitThunk]
7752BD99 [Unknown function at RtlInitializeExceptionChain]
7752BD6C [Unknown function at RtlInitializeExceptionChain]

The object was subsequently freed by thread 0xA34, and the stack trace (return addresses) at the time was:
403E06 
405D71 
406399 
405DAA 
42243B [Project41.dpr][Project41][Project41.Project41][48]
772B86E3 [BaseThreadInitThunk]
7752BD99 [Unknown function at RtlInitializeExceptionChain]
7752BD6C [Unknown function at RtlInitializeExceptionChain]

The current thread ID is 0xA34, and the stack trace (return addresses) leading to this error is:
422447 [Project41.dpr][Project41][Project41.Project41][49]
772B86E3 [BaseThreadInitThunk]
7752BD99 [Unknown function at RtlInitializeExceptionChain]
7752BD6C [Unknown function at RtlInitializeExceptionChain]

Current memory dump of 256 bytes starting at pointer address 7FE8CCD0:
7C B2 42 00 70 B5 42 00 70 B5 42 00 70 B5 42 00 70 B5 42 00 59 22 AC B1 00 00 00 00 91 CD E8 7F
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 76 00 00 00 EA 3D 40 00 6F 70 40 00 58 72 40 00
2F 73 40 00 50 25 52 77 B6 55 52 77 61 88 55 77 40 C2 4F 77 EE 56 52 77 EE 56 52 77 9D 53 52 77
34 0A 00 00 34 0A 00 00 06 3E 40 00 11 71 40 00 57 50 40 00 84 51 40 00 B4 54 40 00 E2 F8 41 00
2F 24 42 00 E3 86 2B 77 99 BD 52 77 6C BD 52 77 00 00 00 00 10 00 00 00 B0 04 02 00 2D 06 C4 2B
7C B2 42 00 70 B5 42 00 70 B5 42 00 70 B5 42 00 D2 F9 3B D4 70 B5 42 00 00 00 00 00 31 CE E8 7F
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 77 00 00 00 B0 70 40 00 63 77 40 00 C8 73 40 00
12 54 40 00 6B 53 40 00 28 50 40 00 84 51 40 00 B4 54 40 00 E2 F8 41 00 2F 24 42 00 E3 86 2B 77
|  І  B  .  p  µ  B  .  p  µ  B  .  p  µ  B  .  p  µ  B  .  Y  "  ¬  ±  .  .  .  .  ‘  Н  и  
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