GNU STL vector push_back insert

push_back

void push_back(value_type &&__x){    emplace_back(std::move(__x));}#if __cplusplus >= 201103Ltemplate <typename _Tp, typename _Alloc>template <typename... _Args>void vector<_Tp, _Alloc>::emplace_back(_Args&&... __args){    if(this->_M_impl._M_finish != this->_M_impl._M_end_of_storage){        _Alloc_traits::construct(this->_M_impl,                                 this->_M_impl._M_finish,                                 std::forward<_Args>(__args)...);        ++this->_M_impl._M_finish;    }else{        _M_emplace_back_aux(std::forward<_Args>(__args)...);    }}#endif