Exceptions during Finalize(): what methodology are you using to detect garbage collector-time exceptions?

Question

I am developing a pretty extensive system in .NET, which involves a lot of system programming. Most time, I\'m using the IDisposable pattern to handle resource disposal, but

Answer 1

Your question is based on a somewhat faulty premise, that is it's not possible to to handle each scenario where a Finalizer might throw. This is precisely what you need to achieve here. Exceptions which occur during finalization will kill the process. Unless the exception is truly fatal, in which case let the program crash, you should be handling this exception in a manner that will not crash your program.

Having a Finalizer throw is almost as bad as having C++ destructors throw. Most implementations of IDisposable call into the same method for both active (IDisposable.Dispose()) and passive (finalizer thread) dispose operations. If the Finalizer version is throwing then it's likely or possible that the active dispose could throw as well. This, much like a C++ destructor throwing, will prevent nested resources from being disposed properly in certain cases.

Don't allow exceptions to propagate from a finalizer unless they are truly fatal to your application.