下面的win32静态库空的，缺省设置，不使用MFCdll或lib
但是用一个MFC控制台（非mfc的没问题）去调用这个友员函数的时候，连接出错，见后面的贴的（VC6）
奇怪的是如果我的那个lib如果在setting中开启Using MFC in shared Dll那么在编译，再连接就有问题
我的lib里面就两个文件mylib.cpp和mylib.h其他缺省里面就下面的一个类
#include <iostream>class mylib {public:mylib() {};virtual ~mylib() {};
friend std::ostream& operator<< (std::ostream& os,mylib& m);
};
=========================================#include "stdafx.h"#include "test.h"
#include "../mylib/mylib.h"
#ifdef _DEBUG#define new DEBUG_NEW#undef THIS_FILEstatic char THIS_FILE[] = __FILE__;#endif
/// The one and only application object
CWinApp theApp;
using namespace std;
int _tmain(int argc, TCHAR* argv[], TCHAR* envp[]){int nRetCode = 0;
// initialize MFC and print and error on failureif (!AfxWinInit(::GetModuleHandle(NULL), NULL, ::GetCommandLine(), 0)){// TODO: change error code to suit your needscerr << _T("Fatal Error: MFC initialization failed") << endl;nRetCode = 1;}else{// TODO: code your application's behavior here.mylib m;cerr<<m;}
return nRetCode;}--------------------Configuration: test - Win32 Debug--------------------Linking...msvcprtd.lib(MSVCP60D.dll) : error LNK2005: "public: class std::basic_ostream<char,struct std::char_traits<char> > & __thiscall std::basic_ostream<char,struct std::char_traits<char> >::operator<<(class std::basic_ostream<char,struct std::char_traits<char> > & (__cdecl*)(class std::basic_ostream<char,struct std::char_traits<char> > &))" (??6?$basic_ostream@DU?$char_traits@D@std@@@std@@QAEAAV01@P6AAAV01@AAV01@@Z@Z) already defined in mylib.lib(mylib.obj)msvcprtd.lib(MSVCP60D.dll) : error LNK2005: "class std::basic_ostream<char,struct std::char_traits<char> > & __cdecl std::operator<<(class std::basic_ostream<char,struct std::char_traits<char> > &,char const *)" (??6std@@YAAAV?$basic_ostream@DU?$char_traits@D@std@@@0@AAV10@PBD@Z) already defined in mylib.lib(mylib.obj)msvcprtd.lib(MSVCP60D.dll) : error LNK2005: "class std::basic_ostream<char,struct std::char_traits<char> > & __cdecl std::endl(class std::basic_ostream<char,struct std::char_traits<char> > &)" (?endl@std@@YAAAV?$basic_ostream@DU?$char_traits@D@std@@@1@AAV21@@Z) already defined in mylib.lib(mylib.obj)libcpd.lib(locale0.obj) : error LNK2005: "public: class std::locale::facet const * __thiscall std::locale::_Getfacet(unsigned int,bool)const " (?_Getfacet@locale@std@@QBEPBVfacet@12@I_N@Z) already defined in msvcprtd.lib(MSVCP60D.dll)libcpd.lib(locale0.obj) : error LNK2005: "public: bool __thiscall std::locale::_Iscloc(void)const " (?_Iscloc@locale@std@@QBE_NXZ) already defined in msvcprtd.lib(MSVCP60D.dll)LIBCD.lib(crt0dat.obj) : error LNK2005: _exit already defined in msvcrtd.lib(MSVCRTD.dll)LIBCD.lib(crt0dat.obj) : error LNK2005: __exit already defined in msvcrtd.lib(MSVCRTD.dll)LIBCD.lib(crt0init.obj) : error LNK2005: ___xc_z already defined in msvcrtd.lib(cinitexe.obj)LIBCD.lib(crt0init.obj) : error LNK2005: ___xc_a already defined in msvcrtd.lib(cinitexe.obj)LIBCD.lib(crt0init.obj) : error LNK2005: ___xi_z already defined in msvcrtd.lib(cinitexe.obj)LIBCD.lib(crt0init.obj) : error LNK2005: ___xi_a already defined in msvcrtd.lib(cinitexe.obj)LIBCD.lib(winxfltr.obj) : error LNK2005: __XcptFilter already defined in msvcrtd.lib(MSVCRTD.dll)LIBCD.lib(crt0.obj) : error LNK2005: _mainCRTStartup already defined in msvcrtd.lib(crtexe.obj)LINK : warning LNK4098: defaultlib "msvcrtd.lib" conflicts with use of other libs; use /NODEFAULTLIB:libraryLINK : warning LNK4098: defaultlib "LIBCD" conflicts with use of other libs; use /NODEFAULTLIB:libraryDebug/test.exe : fatal error LNK1169: one or more multiply defined symbols foundError executing link.exe.
test.exe - 14 error(s), 2 warning(s)
查了一下mylib.lib和test的配置，如下图mylib.lib：
test：
把mylib.lib的配置改成DMD就行了。
