工程中的LINK异常

求教：工程中的LINK错误

建一个工程，在stdafx.h中定义了如下的变量：
extern EPIRPSystemImpl* g_EPIRPSystemImpl = 0
extern AlarmIRPSystemImpl* g_AlarmIRPSystemImpl = 0; ;
extern NotificationIRPSystemImpl* g_NotificationIRPSystemImpl = new 0;
extern BasicCmIRPSystemImpl* g_BasicCmIRPSystemImpl = 0;
当然EPIRPSystemImpl、AlarmIRPSystemImpl、NotificationIRPSystemImpl、BasicCmIRPSystemImpl这些类已经在其他.h中实现，并且已经包含

随后，在CDocument的派生类中声明这几个类成员
class CM31_SimulatorDoc : public CDocument
{
protected: // 仅从序列化创建
CM31_SimulatorDoc();
DECLARE_DYNCREATE(CM31_SimulatorDoc)

// 属性
public:
  const char *str;

EPIRPSystemImpl* g_EPIRPSystemImpl;
  AlarmIRPSystemImpl* g_AlarmIRPSystemImpl; ;
  NotificationIRPSystemImpl* g_NotificationIRPSystemImpl;
  BasicCmIRPSystemImpl* g_BasicCmIRPSystemImpl; 

void export_object(
  PortableServer::POA_ptr poa,
  const PortableServer::ObjectId& oid,
  const char* objref_file,
  const char* type_id
  );

DWORD WINAPI CrbThread(LPVOID lpP);

// 操作
public:
....


并且在对应的.cxx文件中实现这些函数export_object、CrbThread
void
CM31_SimulatorDoc::export_object(
  PortableServer::POA_ptr poa,
  const PortableServer::ObjectId& oid,
  const char* objref_file,
  const char* type_id
)
{
  CORBA::Object_var ref = poa->create_reference_with_id(oid, type_id);
  CORBA::String_var stringified_ref = global_orb->object_to_string(ref);
  cout << "Writing stringified object reference to " << objref_file << endl;
   
  IT_ofstream os(objref_file);
  os << stringified_ref;
  if (!os.good())
  {
cerr << "Failed to write to " << objref_file << endl;
  }
}


DWORD WINAPI CM31_SimulatorDoc::CrbThread(LPVOID lpP)
{
int argc = 0;
char* argv[4];
  global_orb = CORBA::ORB_init(argc,argv);
  CORBA::Object_var objPoa = global_orb->resolve_initial_references("RootPOA");
  root_poa = PortableServer::POA::_narrow(objPoa.in());
  PortableServer::POAManager_var poa_manager = root_poa->the_POAManager();

/***************************************
  * Create Persistent POA by tengwen *
***************************************/

CORBA::PolicyList policies(2);
  policies.length(2);
  policies[0] = root_poa->create_lifespan_policy(PortableServer::PERSISTENT);
  policies[1] = root_poa->create_id_assignment_policy(PortableServer::USER_ID);
PortableServer::POA_var persistent_poa =root_poa->create_POA("persistent",poa_manager,policies);

  g_EPIRPSystemImpl = new EPIRPSystemImpl();
g_AlarmIRPSystemImpl = new AlarmIRPSystemImpl();  
g_NotificationIRPSystemImpl = new NotificationIRPSystemImpl();
g_BasicCmIRPSystemImpl = new BasicCmIRPSystemImpl();
//log_string = "Create all IRP Implement Successfully...";
  //OutputDebugString("hello kitty");

/********************************************************************************************
  * Create and activate EPIRPSystemImpl、NotificationIRPSystemImpl、AlarmIRPSystemImpl *
  * and BasicCmIRPSystemImpl object and the save EPIRPSystemImpl IOR to ftp server folder *
********************************************************************************************/

PortableServer::ObjectId_var inherit_oid = root_poa->activate_object(g_EPIRPSystemImpl);