Using Boost 1.30.0. MSVC6 Tow problems: (1) I have to #define __WIN32__, and (2) Doesn't compile Am I doing something wrong, here? #include "afxwin.h" #include <map> #define __WIN32__ // why do I have to define this??? #include "boost/pool/pool_alloc.hpp" int main() { std::map<int,int,std::less<int>, boost::pool_allocator<int> > return 0; } :\Program Files\Microsoft Visual Studio\VC98\INCLUDE\xtree(587) : error C2664: 'deallocate' : cannot convert parameter 1 from 'struct std::_Tree<int,struct std::pair<int const ,int>,struct std::map<int,int,struct std::less<int>,class boost::pool_al locator<int,struct boost::default_user_allocator_new_delete,class boost::details::pool::win32_mutex,32> >::_Kfn,struct std::less<int>,class boost::pool_allocator<int,struct boost::default_user_allocator_new_delete,class boost::details::pool::win32_m utex,32> >::_Node *' to 'int *const ' Types pointed to are unrelated; conversion requires reinterpret_cast, C-style cast or function-style cast C:\Program Files\Microsoft Visual Studio\VC98\INCLUDE\xtree (587) : while compiling class-template member function 'void __thiscall std::_Tree<int,struct std::pair<int const ,int>,struct std::map<int,int,struct std::less<int>,class boost::poo l_allocator<int,struct boost::default_user_allocator_new_delete,class boost::details::pool::win32_mutex,32> >::_Kfn,struct std::less<int>,class boost::pool_allocator<int,struct boost::default_user_allocator_new_delete,class boost::details::pool::win 32_mutex,32> >::_Freenode(struct std::_Tree<int,struct std::pair<int const ,int>,struct std::map<int,int,struct std::less<int>,class boost::pool_allocator<int,struct boost::default_user_allocator_new_delete,class boost::details::pool::win32_mutex,32

...

::_Kfn,struct std::less<int>,class boost::pool_allocator<int,struct boost::default_user_allocator_new_delete,class boost::details::pool::win32_mutex,32> >::_Node *)'