如何修复 Visual Studio 2012 错误 LNK2019：无法解析的外部符号“__declspec(dllimport) public: class std::basic_string?答案

【问题标题】：How to Fix Visual Studio 2012 error LNK2019: unresolved external symbol "__declspec(dllimport) public: class std::basic_string?如何修复 Visual Studio 2012 错误 LNK2019：无法解析的外部符号“__declspec(dllimport) public: class std::basic_string?
【发布时间】：2013-03-09 21:48:24
【问题描述】：

如何修复 Visual Studio 2012 错误 LNK2019: unresolved external symbol "__declspec(dllimport) public: class std::basic_string?

我一直在编译一个包含一个 exe 和几个静态库项目的解决方案 exe 依赖于 Visual Studio 2008。静态库包括：

TCL：tcl84tsx.lib
wxWidgets: wxbase.lib
zlib.lib
ws2_32.lib
xerces-c_2.lib
SNMP 研究 EMANATE：subagent.lib,agent.lib,emanate.lib,pack.lib,mibtable.lib,devkit.lib
等

我将解决方案加载到 Visual Studio 2012 并编译了解决方案中的所有项目，但是当我尝试链接 exe 时，我收到有关标准 C++ 库中的东西的未解析符号的错误，如下面的输出。

我发现很多人都有像这样的未解决符号，但没有一个修复对我有用。到目前为止我尝试过的修复包括

通过手动添加对 exe 项目所依赖的静态库项目的引用来更新 EXE 项目
切换“将 wchar_t 视为内置类型”链接器选项

Visual Studio 2012 链接器的输出...

 1>ace_funcs.obj : warning LNK4075: ignoring '/EDITANDCONTINUE' due to '/OPT:LBR' specification
 1>LINK : warning LNK4098: defaultlib 'MSVCRT' conflicts with use of other libs; use /NODEFAULTLIB:library
 1>ComponentX-Win32.lib(MyOrgConsoleSktServer.obj) : warning LNK4049: locally defined symbol ??0?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@QAE@ABV01@@Z (public: __thiscall std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &)) imported
 1>ComponentY-Win32.lib(ORBSingleton.obj) : warning LNK4049: locally defined symbol ??0?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@QAE@ABV01@@Z (public: __thiscall std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &)) imported
 1>ComponentY-Win32.lib(OrbException.obj) : warning LNK4049: locally defined symbol ??0?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@QAE@ABV01@@Z (public: __thiscall std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &)) imported
 1>ComponentZ-Win32.lib(ExceptionHelper.obj) : warning LNK4049: locally defined symbol ??0?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@QAE@ABV01@@Z (public: __thiscall std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &)) imported
 1>ComponentZ-Win32.lib(ComponentCCheckpointImpl.obj) : warning LNK4217: locally defined symbol ??0?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@QAE@ABV01@@Z (public: __thiscall std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &)) imported in function "public: __thiscall std::logic_error::logic_error(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &)" (??0logic_error@std@@QAE@ABV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@1@@Z)
 1>ComponentX-Win32.lib(MyOrgConsole.obj) : warning LNK4049: locally defined symbol ??0?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@QAE@ABV01@@Z (public: __thiscall std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &)) imported
 1>ComponentX-Win32.lib(MyOrgThreadFactory.obj) : warning LNK4049: locally defined symbol ??0?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@QAE@ABV01@@Z (public: __thiscall std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &)) imported
 1>ComponentZ-Win32.lib(PersistenceServiceProxy.obj) : warning LNK4049: locally defined symbol ??0?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@QAE@ABV01@@Z (public: __thiscall std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &)) imported
 1>ComponentZ-Win32.lib(ComponentBServiceImpl.obj) : warning LNK4049: locally defined symbol ??0?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@QAE@ABV01@@Z (public: __thiscall std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &)) imported
 1>ComponentZ-Win32.lib(XmlPreferencesHelper.obj) : warning LNK4217: locally defined symbol ??0?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@QAE@ABV01@@Z (public: __thiscall std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &)) imported in function "private: void __thiscall _CORBA_Sequence_String::copybuffer(unsigned long)" (?copybuffer@_CORBA_Sequence_String@@AAEXK@Z)
 1>ComponentZ-Win32.lib(XmlHelper.obj) : warning LNK4049: locally defined symbol ??0?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@QAE@ABV01@@Z (public: __thiscall std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &)) imported
 1>ComponentA-Win32.lib(ServiceBootstrap.obj) : warning LNK4217: locally defined symbol ??0?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@QAE@ABV01@@Z (public: __thiscall std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &)) imported in function "public: __thiscall std::logic_error::logic_error(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &)" (??0logic_error@std@@QAE@ABV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@1@@Z)
 1>ComponentA-Win32.lib(propertyutil.obj) : warning LNK4049: locally defined symbol ??0?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@QAE@ABV01@@Z (public: __thiscall std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &)) imported
 1>ComponentA-Win32.lib(SystemEnvironment.obj) : warning LNK4049: locally defined symbol ??0?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@QAE@ABV01@@Z (public: __thiscall std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &)) imported
 1>ComponentZ-Win32.lib(PersistenceClient.obj) : warning LNK4049: locally defined symbol ??0?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@QAE@ABV01@@Z (public: __thiscall std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &)) imported
 1>ComponentY-Win32.lib(OrbException.obj) : warning LNK4049: locally defined symbol ??1?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@QAE@XZ (public: __thiscall std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >::~basic_string<char,struct std::char_traits<char>,class std::allocator<char> >(void)) imported
 1>ComponentX-Win32.lib(MyOrgConsole.obj) : warning LNK4049: locally defined symbol ??1?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@QAE@XZ (public: __thiscall std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >::~basic_string<char,struct std::char_traits<char>,class std::allocator<char> >(void)) imported
 1>ComponentX-Win32.lib(MyOrgThreadFactory.obj) : warning LNK4049: locally defined symbol ??1?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@QAE@XZ (public: __thiscall std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >::~basic_string<char,struct std::char_traits<char>,class std::allocator<char> >(void)) imported
 1>ComponentX-Win32.lib(MyOrgConsoleSktServer.obj) : warning LNK4049: locally defined symbol ??1?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@QAE@XZ (public: __thiscall std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >::~basic_string<char,struct std::char_traits<char>,class std::allocator<char> >(void)) imported
 1>ComponentY-Win32.lib(ORBSingleton.obj) : warning LNK4217: locally defined symbol ??1?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@QAE@XZ (public: __thiscall std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >::~basic_string<char,struct std::char_traits<char>,class std::allocator<char> >(void)) imported in function "public: virtual __thiscall OrbException::~OrbException(void)" (??1OrbException@@UAE@XZ)
 1>ComponentZ-Win32.lib(XmlPreferencesHelper.obj) : warning LNK4049: locally defined symbol ??1?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@QAE@XZ (public: __thiscall std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >::~basic_string<char,struct std::char_traits<char>,class std::allocator<char> >(void)) imported
 -- snip --
 1>ComponentA-Win32.lib(ServiceBootstrap.obj) : error LNK2019: unresolved external symbol "__declspec(dllimport) public: class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > __thiscall std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >::substr(unsigned int,unsigned int)const " (__imp_?substr@?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@QBE?AV12@II@Z) referenced in function "private: class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > __thiscall ServiceBootstrap::trimmed(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &,char const *)" (?trimmed@ServiceBootstrap@@AAE?AV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@ABV23@PBD@Z)
 1>ComponentA-Win32.lib(ServiceBootstrap.obj) : error LNK2019: unresolved external symbol "__declspec(dllimport) public: unsigned int __thiscall std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >::find_last_not_of(char const *,unsigned int,unsigned int)const " (__imp_?find_last_not_of@?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@QBEIPBDII@Z) referenced in function "private: class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > __thiscall ServiceBootstrap::trimmed(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &,char const *)" (?trimmed@ServiceBootstrap@@AAE?AV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@ABV23@PBD@Z)
 1>ComponentA-Win32.lib(ServiceBootstrap.obj) : error LNK2019: unresolved external symbol "__declspec(dllimport) public: unsigned int __thiscall std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >::find_first_not_of(char const *,unsigned int,unsigned int)const " (__imp_?find_first_not_of@?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@QBEIPBDII@Z) referenced in function "private: class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > __thiscall ServiceBootstrap::trimmed(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &,char const *)" (?trimmed@ServiceBootstrap@@AAE?AV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@ABV23@PBD@Z)
 1>ComponentA-Win32.lib(ServiceBootstrap.obj) : error LNK2019: unresolved external symbol "__declspec(dllimport) class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > __cdecl std::operator+<char,struct std::char_traits<char>,class std::allocator<char> >(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &,char const *)" (__imp_??$?HDU?$char_traits@D@std@@V?$allocator@D@1@@std@@YA?AV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@0@ABV10@PBD@Z) referenced in function "private: void __thiscall ServiceBootstrap::verifyBootstrapProperties(void)" (?verifyBootstrapProperties@ServiceBootstrap@@AAEXXZ)
 1>ComponentZ-Win32.lib(PersistenceServiceProxy.obj) : error LNK2001: unresolved external symbol "__declspec(dllimport) class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > __cdecl std::operator+<char,struct std::char_traits<char>,class std::allocator<char> >(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &,char const *)" (__imp_??$?HDU?$char_traits@D@std@@V?$allocator@D@1@@std@@YA?AV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@0@ABV10@PBD@Z)
 1>ComponentA-Win32.lib(ServiceBootstrap.obj) : error LNK2019: unresolved external symbol "__declspec(dllimport) class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > __cdecl std::operator+<char,struct std::char_traits<char>,class std::allocator<char> >(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &,class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &)" (__imp_??$?HDU?$char_traits@D@std@@V?$allocator@D@1@@std@@YA?AV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@0@ABV10@0@Z) referenced in function "public: class std::map<class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >,class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >,struct std::less<class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > >,class std::allocator<struct std::pair<class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const ,class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > > > > __thiscall ServiceBootstrap::getBootstrapProperties(void)" (?getBootstrapProperties@ServiceBootstrap@@QAE?AV?$map@V?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@V12@U?$less@V?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@@2@V?$allocator@U?$pair@$$CBV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@V12@@std@@@2@@std@@XZ)
 1>ComponentZ-Win32.lib(PersistenceServiceProxy.obj) : error LNK2001: unresolved external symbol "__declspec(dllimport) class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > __cdecl std::operator+<char,struct std::char_traits<char>,class std::allocator<char> >(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &,class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &)" (__imp_??$?HDU?$char_traits@D@std@@V?$allocator@D@1@@std@@YA?AV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@0@ABV10@0@Z)
 1>ComponentA-Win32.lib(propertyutil.obj) : error LNK2019: unresolved external symbol "__declspec(dllimport) public: void __thiscall std::_Mutex::_Lock(void)" (__imp_?_Lock@_Mutex@std@@QAEXXZ) referenced in function "public: __thiscall std::basic_ostream<char,struct std::char_traits<char> >::_Sentry_base::_Sentry_base(class std::basic_ostream<char,struct std::char_traits<char> > &)" (??0_Sentry_base@?$basic_ostream@DU?$char_traits@D@std@@@std@@QAE@AAV12@@Z)
 1>ComponentZ-Win32.lib(XmlHelper.obj) : error LNK2001: unresolved external symbol "__declspec(dllimport) public: void __thiscall std::_Mutex::_Lock(void)" (__imp_?_Lock@_Mutex@std@@QAEXXZ)
 -- snip --
 1>.\Debug/sComponentC.exe : fatal error LNK1120: 22 unresolved externals
 ========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========

【问题讨论】：

尝试从包含语句中删除任何 .h 文件
在项目属性中，将 Platform Toolset 设置为 VS2008 (v90) 并根据您的安装设置正确的目录（即：include => C:\Program Files (x86)\Windows Kits\8.0\Include\shared;C:\Program Files (x86)\Windows Kits\8.0\Include\um;$(IncludePath) 和库 = > C:\Program Files (x86)\Windows Kits\8.0\Lib\win8\um\x64;$(LibraryPath))。不要忘记在链接条目中设置 .lib。
在谷歌搜索时，我看到了 Platform Toolset 技巧。在这家大公司中，为 MSVC++ 设置 MSI 的人似乎没有包含 v90。所以我的 MSBuild 文件夹只有 v10 的工具集定义。我会尝试追踪它。或者，如果我能找出链接器问题，我可以重新构建所有依赖项。
>尝试从包含语句中删除任何 .h 我没有看到任何 .h 是罪魁祸首的情况。我会继续寻找。
类似问题：stackoverflow.com/questions/13634193/linker-error-lnk2001

标签： visual-studio-2012 unresolved-external lnk2019 c++-standard-library stdstring

【解决方案1】：

在 properties->c/c++->Laguage 中，我将treat wchar_t as built in type 设置为 No，它解决了我的问题。

【讨论】：

【解决方案2】：

如果您已经尝试过以下选项：

通过手动添加对 exe 项目所依赖的静态库项目的引用来更新 EXE 项目
切换“将 wchar_t 视为内置类型”选项

尝试按照以下步骤将您的项目配置为 x64：

右击Solution 'ProjectName'
选择Configuration Manager...
将您尝试将.lib 文件链接到x64 的项目的platform 从Win32 更改（反之亦然）
重建解决方案

这实际上解决了我的问题。我不知道我的外部库是针对 32 位还是 64 位编译的。

【讨论】：

【解决方案3】：

即使我在 Visual Studio 中也遇到过这种类型的错误。出现此类错误的原因是，

1) 您可能包含了多个相互冲突的库。有时，一个库中的一个类可能会与另一个库中的另一个类发生冲突。

2) 您可能已包含目录中的库。再次检查库的路径。

3) 您需要在项目属性中指定库和头文件（如果必须包含）。再次检查路径是否正确。

【讨论】：