VS2008, 写一个简单的demo的时候出现了这个:

1>------ Build started: Project: GetExportTable, Configuration: Release Win32 ------
1>Compiling...
1>main.cpp
1>e:\tzcode\getexporttable\getexporttable\GetExportTable.h(61) : warning C4996: 'scanf': This function or variable may be unsafe. Consider using scanf_s instead. To disable deprecation, use _CRT_SECURE_NO_WARNINGS. See online help for details.
1> E:\TzSoft\VS2008\VC\include\stdio.h(306) : see declaration of 'scanf'
1>E:\TzSoft\VS2008\VC\include\functional(143) : error C2784: 'bool std::operator <(const std::_Tree<_Traits> &,const std::_Tree<_Traits> &)' : could not deduce template argument for 'const std::_Tree<_Traits> &' from 'const std::string'
1> E:\TzSoft\VS2008\VC\include\xtree(1466) : see declaration of 'std::operator <'
1> E:\TzSoft\VS2008\VC\include\functional(142) : while compiling class template member function 'bool std::less<_Ty>::operator ()(const _Ty &,const _Ty &) const'
1> with
1> [
1> _Ty=std::string
1> ]
1> E:\TzSoft\VS2008\VC\include\map(68) : see reference to class template instantiation 'std::less<_Ty>' being compiled
1> with
1> [
1> _Ty=std::string
1> ]
1> E:\TzSoft\VS2008\VC\include\xtree(22) : see reference to class template instantiation 'std::_Tmap_traits<_Kty,_Ty,_Pr,_Alloc,_Mfl>' being compiled
1> with
1> [
1> _Kty=std::string,
1> _Ty=int,
1> _Pr=std::less<std::string>,
1> _Alloc=std::allocator<std::pair<const std::string,int>>,
1> _Mfl=false
1> ]
1> E:\TzSoft\VS2008\VC\include\xtree(63) : see reference to class template instantiation 'std::_Tree_nod<_Traits>' being compiled
1> with
1> [
1> _Traits=std::_Tmap_traits<std::string,int,std::less<std::string>,std::allocator<std::pair<const std::string,int>>,false>
1> ]
1> E:\TzSoft\VS2008\VC\include\xtree(89) : see reference to class template instantiation 'std::_Tree_ptr<_Traits>' being compiled
1> with
1> [
1> _Traits=std::_Tmap_traits<std::string,int,std::less<std::string>,std::allocator<std::pair<const std::string,int>>,false>
1> ]
1> E:\TzSoft\VS2008\VC\include\xtree(107) : see reference to class template instantiation 'std::_Tree_val<_Traits>' being compiled
1> with
1> [
1> _Traits=std::_Tmap_traits<std::string,int,std::less<std::string>,std::allocator<std::pair<const std::string,int>>,false>
1> ]
1> E:\TzSoft\VS2008\VC\include\map(78) : see reference to class template instantiation 'std::_Tree<_Traits>' being compiled
1> with
1> [
1> _Traits=std::_Tmap_traits<std::string,int,std::less<std::string>,std::allocator<std::pair<const std::string,int>>,false>
1> ]
1> .\main.cpp(65) : see reference to class template instantiation 'std::map<_Kty,_Ty>' being compiled
1> with
1> [
1> _Kty=std::string,
1> _Ty=int
1> ]
1>E:\TzSoft\VS2008\VC\include\functional(143) : error C2784: 'bool std::operator <(const std::_Tree<_Traits> &,const std::_Tree<_Traits> &)' : could not deduce template argument for 'const std::_Tree<_Traits> &' from 'const std::string'
1> E:\TzSoft\VS2008\VC\include\xtree(1466) : see declaration of 'std::operator <'
1>E:\TzSoft\VS2008\VC\include\functional(143) : error C2784: 'bool std::operator <(const std::_Tree<_Traits> &,const std::_Tree<_Traits> &)' : could not deduce template argument for 'const std::_Tree<_Traits> &' from 'const std::string'
1> E:\TzSoft\VS2008\VC\include\xtree(1466) : see declaration of 'std::operator <'
1>E:\TzSoft\VS2008\VC\include\functional(143) : error C2784: 'bool std::operator <(const std::_Tree<_Traits> &,const std::_Tree<_Traits> &)' : could not deduce template argument for 'const std::_Tree<_Traits> &' from 'const std::string'
1> E:\TzSoft\VS2008\VC\include\xtree(1466) : see declaration of 'std::operator <'
1>E:\TzSoft\VS2008\VC\include\functional(143) : error C2784: 'bool std::operator <(const std::vector<_Ty,_Alloc> &,const std::vector<_Ty,_Alloc> &)' : could not deduce template argument for 'const std::vector<_Ty,_Alloc> &' from 'const std::string'
1> E:\TzSoft\VS2008\VC\include\vector(1320) : see declaration of 'std::operator <'
1>E:\TzSoft\VS2008\VC\include\functional(143) : error C2784: 'bool std::operator <(const std::vector<_Ty,_Alloc> &,const std::vector<_Ty,_Alloc> &)' : could not deduce template argument for 'const std::vector<_Ty,_Alloc> &' from 'const std::string'
1> E:\TzSoft\VS2008\VC\include\vector(1320) : see declaration of 'std::operator <'
1>E:\TzSoft\VS2008\VC\include\functional(143) : error C2784: 'bool std::operator <(const std::vector<_Ty,_Alloc> &,const std::vector<_Ty,_Alloc> &)' : could not deduce template argument for 'const std::vector<_Ty,_Alloc> &' from 'const std::string'
1> E:\TzSoft\VS2008\VC\include\vector(1320) : see declaration of 'std::operator <'
1>E:\TzSoft\VS2008\VC\include\functional(143) : error C2784: 'bool std::operator <(const std::vector<_Ty,_Alloc> &,const std::vector<_Ty,_Alloc> &)' : could not deduce template argument for 'const std::vector<_Ty,_Alloc> &' from 'const std::string'
1> E:\TzSoft\VS2008\VC\include\vector(1320) : see declaration of 'std::operator <'
1>E:\TzSoft\VS2008\VC\include\functional(143) : error C2784: 'bool std::operator <(const std::list<_Ty,_Ax> &,const std::list<_Ty,_Ax> &)' : could not deduce template argument for 'const std::list<_Ty,_Ax> &' from 'const std::string'
1> E:\TzSoft\VS2008\VC\include\list(1310) : see declaration of 'std::operator <'
1>E:\TzSoft\VS2008\VC\include\functional(143) : error C2784: 'bool std::operator <(const std::list<_Ty,_Ax> &,const std::list<_Ty,_Ax> &)' : could not deduce template argument for 'const std::list<_Ty,_Ax> &' from 'const std::string'
1> E:\TzSoft\VS2008\VC\include\list(1310) : see declaration of 'std::operator <'
1>E:\TzSoft\VS2008\VC\include\functional(143) : error C2784: 'bool std::operator <(const std::list<_Ty,_Ax> &,const std::list<_Ty,_Ax> &)' : could not deduce template argument for 'const std::list<_Ty,_Ax> &' from 'const std::string'
1> E:\TzSoft\VS2008\VC\include\list(1310) : see declaration of 'std::operator <'
1>E:\TzSoft\VS2008\VC\include\functional(143) : error C2784: 'bool std::operator <(const std::list<_Ty,_Ax> &,const std::list<_Ty,_Ax> &)' : could not deduce template argument for 'const std::list<_Ty,_Ax> &' from 'const std::string'
1> E:\TzSoft\VS2008\VC\include\list(1310) : see declaration of 'std::operator <'
1>E:\TzSoft\VS2008\VC\include\functional(143) : error C2784: 'bool std::operator <(const std::reverse_iterator<_RanIt> &,const std::reverse_iterator<_RanIt2> &)' : could not deduce template argument for 'const std::reverse_iterator<_RanIt> &' from 'const std::string'
1> E:\TzSoft\VS2008\VC\include\xutility(2236) : see declaration of 'std::operator <'
1>E:\TzSoft\VS2008\VC\include\functional(143) : error C2784: 'bool std::operator <(const std::reverse_iterator<_RanIt> &,const std::reverse_iterator<_RanIt2> &)' : could not deduce template argument for 'const std::reverse_iterator<_RanIt> &' from 'const std::string'
1> E:\TzSoft\VS2008\VC\include\xutility(2236) : see declaration of 'std::operator <'
1>E:\TzSoft\VS2008\VC\include\functional(143) : error C2784: 'bool std::operator <(const std::reverse_iterator<_RanIt> &,const std::reverse_iterator<_RanIt2> &)' : could not deduce template argument for 'const std::reverse_iterator<_RanIt> &' from 'const std::string'
1> E:\TzSoft\VS2008\VC\include\xutility(2236) : see declaration of 'std::operator <'
1>E:\TzSoft\VS2008\VC\include\functional(143) : error C2784: 'bool std::operator <(const std::reverse_iterator<_RanIt> &,const std::reverse_iterator<_RanIt2> &)' : could not deduce template argument for 'const std::reverse_iterator<_RanIt> &' from 'const std::string'
1> E:\TzSoft\VS2008\VC\include\xutility(2236) : see declaration of 'std::operator <'
1>E:\TzSoft\VS2008\VC\include\functional(143) : error C2784: 'bool std::operator <(const std::_Revranit<_RanIt,_Base> &,const std::_Revranit<_RanIt2,_Base2> &)' : could not deduce template argument for 'const std::_Revranit<_RanIt,_Base> &' from 'const std::string'
1> E:\TzSoft\VS2008\VC\include\xutility(2046) : see declaration of 'std::operator <'
1>E:\TzSoft\VS2008\VC\include\functional(143) : error C2784: 'bool std::operator <(const std::_Revranit<_RanIt,_Base> &,const std::_Revranit<_RanIt2,_Base2> &)' : could not deduce template argument for 'const std::_Revranit<_RanIt,_Base> &' from 'const std::string'
1> E:\TzSoft\VS2008\VC\include\xutility(2046) : see declaration of 'std::operator <'
1>E:\TzSoft\VS2008\VC\include\functional(143) : error C2784: 'bool std::operator <(const std::_Revranit<_RanIt,_Base> &,const std::_Revranit<_RanIt2,_Base2> &)' : could not deduce template argument for 'const std::_Revranit<_RanIt,_Base> &' from 'const std::string'
1> E:\TzSoft\VS2008\VC\include\xutility(2046) : see declaration of 'std::operator <'
1>E:\TzSoft\VS2008\VC\include\functional(143) : error C2784: 'bool std::operator <(const std::_Revranit<_RanIt,_Base> &,const std::_Revranit<_RanIt2,_Base2> &)' : could not deduce template argument for 'const std::_Revranit<_RanIt,_Base> &' from 'const std::string'
1> E:\TzSoft\VS2008\VC\include\xutility(2046) : see declaration of 'std::operator <'
1>E:\TzSoft\VS2008\VC\include\functional(143) : error C2784: 'bool std::operator <(const std::pair<_Ty1,_Ty2> &,const std::pair<_Ty1,_Ty2> &)' : could not deduce template argument for 'const std::pair<_Ty1,_Ty2> &' from 'const std::string'
1> E:\TzSoft\VS2008\VC\include\utility(84) : see declaration of 'std::operator <'
1>E:\TzSoft\VS2008\VC\include\functional(143) : error C2784: 'bool std::operator <(const std::pair<_Ty1,_Ty2> &,const std::pair<_Ty1,_Ty2> &)' : could not deduce template argument for 'const std::pair<_Ty1,_Ty2> &' from 'const std::string'
1> E:\TzSoft\VS2008\VC\include\utility(84) : see declaration of 'std::operator <'
1>E:\TzSoft\VS2008\VC\include\functional(143) : error C2784: 'bool std::operator <(const std::pair<_Ty1,_Ty2> &,const std::pair<_Ty1,_Ty2> &)' : could not deduce template argument for 'const std::pair<_Ty1,_Ty2> &' from 'const std::string'
1> E:\TzSoft\VS2008\VC\include\utility(84) : see declaration of 'std::operator <'
1>E:\TzSoft\VS2008\VC\include\functional(143) : error C2784: 'bool std::operator <(const std::pair<_Ty1,_Ty2> &,const std::pair<_Ty1,_Ty2> &)' : could not deduce template argument for 'const std::pair<_Ty1,_Ty2> &' from 'const std::string'
1> E:\TzSoft\VS2008\VC\include\utility(84) : see declaration of 'std::operator <'
1>E:\TzSoft\VS2008\VC\include\functional(143) : error C2676: binary '<' : 'const std::string' does not define this operator or a conversion to a type acceptable to the predefined operator
1>Build log was saved at "file://e:\TzCode\GetExportTable\GetExportTable\Release\BuildLog.htm"
1>GetExportTable - 25 error(s), 1 warning(s)
========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========

开始把注意力集中在

1>E:\TzSoft\VS2008\VC\include\functional(143) : error C2784: 'bool std::operator <(const std::_Tree<_Traits> &,const std::_Tree<_Traits> &)' : could not deduce template argument for 'const std::_Tree<_Traits> &' from 'const std::string'
1> E:\TzSoft\VS2008\VC\include\xtree(1466) : see declaration of 'std::operator <'

还以为是std::string没了 operator<

又怀疑是否是模板实例化的时候有啥别的问题(const, 类型转化之类的).

最后在网上搜了一下原来是没有#include <string>

但是为啥没报string是未定义标识符?

猜测可能是在哪个头文件里面声明了class string, 但是没有实现. 于是会找不到 string 的operator< .

具体原因有待进一步考证