How to Fix Visual Studio 2012 error LNK2019: unresolved external symbol \"__declspec(dllimport) public: class std::basic_string?

Question

How to fix a Visual Studio 2012 error LNK2019: unresolved external symbol "__declspec(dllimport) public: class std::basic_string?

I've been compiling a solution containing one exe and several static lib projects on which the exe depends fine with Visual Studio 2008. The static libs include:

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

I loaded the solution into Visual Studio 2012 and have compiled all the projects in the solution but when I try to link the exe, I'm getting errors about unresolved symbols for stuff in the standard C++ library like the output below.

I've found lots of people with unresolved symbols like this one but none of the fixes are working for me. Fixes I've tried so far include

• Updating the EXE project by manually adding references to static lib projects on which the exe project depends
• Toggling the "treat wchar_t as built-in type" linker option

Output from Visual Studio 2012 linker...

 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 ==========

Answer 1

In properties->c/c++->Laguage, I set treat wchar_t as built in type to No and it solved my problem.

Answer 2

If you have already tried below options:

• Updating the EXE project by manually adding references to static lib projects on which the exe project depends
• Toggling the "treat wchar_t as built-in type" option

Try configuring your project to x64 by following steps:

• Right click on Solution 'ProjectName'
• Select Configuration Manager...
• Change the platform of the project which you are trying to link .lib file to x64 from Win32 (or vise versa)
• Rebuild the solution

This actually resolved my problem. I wasn't aware if my external lib is compiled for 32-bit or 64-bit.

Answer 3

Even I faced this type of errors in visual studio. The reason for these kind of errors are,

1) You might have included multiple libraries which are conflicting each other. Sometimes,one class in a library can conflict other class in other library.

2) You might have included libraries from directories. Check the path of the libraries once again.

3) You need to specify libraries and header files (if you have to include) in the project properties. Check once again whether the paths are correct.