为什么编译万能头的时候，跳出 ios-base.h 并且编译不过

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C:\Program Files (x86)\Dev-Cpp\MinGW64\lib\gcc\x86_64-w64-mingw32\4.9.2\include\c++\bits\ios_base.h

[Error] field '_M_msg' has incomplete type 'std::string {aka std::basic_string}'