BUG: Methods Calls on Interface with Unloaded Application Domain Cause Access Violation (327098)

MORE INFORMATION

Steps to Reproduce the Behavior

1. Create a new C# Class Library with the name ClassLibrary1.
   
   By default, Class1.cs file is created.
2. You can overwrite the existing code by pasting the following code in Class1.cs:

   using System;
   using System.Reflection;
   
   namespace Library1
   {
   	public interface I0
   	{
   		void DoWork();
   		void DoMoreWork();
   	}
   
   	public class DoWork : MarshalByRefObject, I0
   	{
   		void I0.DoWork() {}
   		void I0.DoMoreWork() {}
   	}
   
   	public interface IObjectServer 
   	{
   		object GetTheObject();
   		void Unload();
   	}
   
   	public class ObjectServer : IObjectServer 
   	{
   		private AppDomain m_ad;
   
   		public virtual object GetTheObject() 
   		{
   			string friendlyName;
   
   			friendlyName = "ObjectServer: " + Guid.NewGuid();
   			m_ad = AppDomain.CreateDomain(friendlyName, null);
   			return m_ad.CreateInstanceFromAndUnwrap(
   				Assembly.GetAssembly(typeof(DoWork)).Location,
   				typeof(DoWork).FullName);
   		}
   
   		public virtual void Unload() 
   		{
   			AppDomain.Unload(m_ad);
   		}
   
   		public ObjectServer() : base() 
   		{
   			m_ad = null;
   		}
   	}
   }
   					

3. Open the Property Pages of the project.
4. Select True in Register for COM Interop of the "Build" section under Configuration Properties.
5. Press CTRL+SHIFT+B to build the solution.
   
   The ClassLibrary1.tlb file is generated as a result of assembly registration.
6. Create a new Console Application that is written in Visual C++, and then paste the following code in the source file:

   #include <stdio.h>
   #include <comdef.h>
   #import "<Path to tlb>\ClassLibrary1.tlb" no_namespace named_guids
   
   void main(void)
   {
   	CoInitialize(NULL);
   
   	IObjectServerPtr pObjSrv;
   	CoCreateInstance(CLSID_ObjectServer, 
         NULL, 
         CLSCTX_ALL, 
         IID_IObjectServer, 
         (void **)&pObjSrv);
   
   	VARIANT var;
   	HRESULT hr = pObjSrv->raw_GetTheObject(&var);
   
   	_DoWorkPtr pWork;
   	pWork = var.pdispVal;
   
   	VariantClear(&var);
   
   	I0Ptr i0;
   	i0 = pWork;
   
   	printf("I0 DoWork\n");
   	i0->DoWork();
   
   //	i0->DoMoreWork();
   //	printf("I0 DoMoreWork\n");
   	
   	printf("AppDomain Unload\n");
   	pObjSrv->Unload();
   
   	printf("I0 DoMoreWork\n");
   	i0->DoMoreWork();
   
   	i0 = NULL;
   
   	CoUninitialize();
   }
   					

7. Compile the code that is written in C++, and then run the .exe file.
   
   You receive the Access Violation that is described in the "Symptoms" section of this article.
8. Uncomment the two lines in the C-language program code, and then check again.
   
   The code fails gracefully if the method has been invoked before. You receive the following error message:
   Microsoft Visual C++ Runtime Library
   
   Runtime Error!
   
   Program: MyTestApp.exe
   
   This application has requested the Runtime to terminate it in an unusual way.
   Please contact the application's support team for more information.