Finalization crash in TB2Acc.pas in TTBCustomAccObject.Destroy on Delphi 10.4.2 64bit

[paveltresnak]

In finalization unit TB2Acc.pas is destroyed critical section LastAccObjectCritSect and after that is calling TTBCustomAccObject.Destroy (releasing interfaces) where is calling EnterCriticalSection(LastAccObjectCritSect). On 32bit are all AccObject released before destroing LastAccObjectCritSect.

[zedxxx]

Isn't this a bug in Delphi x64 compiler?

[zedxxx]

The patch from this issue may help: SilverpointDev/sptbxlib#107

  TTBCustomAccObject = class(TTBBaseAccObject)
    ...
    class var AccessibilityFinalized: Boolean;
  end;

finalization
  DisconnectAccObjects;
  if NeedToUninitialize then
    CoUninitialize;
  if LastAccObject = nil then
    DeleteCriticalSection(LastAccObjectCritSect)
  else
    TTBCustomAccObject.AccessibilityFinalized  := True;

destructor TTBCustomAccObject.Destroy;
begin
  { Remove Self from linked list of objects }
  EnterCriticalSection(LastAccObjectCritSect);
  try
    if LastAccObject = Self then
      LastAccObject := FPrevious;
    if Assigned(FPrevious) then
      FPrevious.FNext := FNext;
    if Assigned(FNext) then
      FNext.FPrevious := FPrevious;
  finally
    LeaveCriticalSection(LastAccObjectCritSect);
  end;
  if AccessibilityFinalized and (LastAccObject = nil) then
    DeleteCriticalSection(LastAccObjectCritSect);
  inherited;
end;