I'm trying to use g++ (and MinGW) to compile a win32 Direct3X program that I've written under Visual C++. All is well (so far) except for one thing. I'm using the technique suggested in the Boost shared_ptr documentation to store pointers to COM objects, which works fine under Visual C++ but under g++ (either 3.4.x or 4.3.x) I get errors about the call to mem_fn being ambiguous due to stdcall / non-stdcall overloading. I can't find any references to this problem on the net so I assume I'm doing something utterly boneheaded. Any hints would be very welcome. For example: #define BOOST_MEM_FN_ENABLE_STDCALL #include <d3d9.h> #include <boost/mem_fn.hpp> #include <boost/shared_ptr.hpp> void test_mem_fn(IDirect3DDevice9 * const device) { boost::shared_ptr<IDirect3DDevice9> ptr( device, boost::mem_fn(&IDirect3DDevice9::Release) ); } test/test_mem_fn.cpp:13: error: call of overloaded 'mem_fn(ULONG (IDirect3DDevice9::*)())' is ambiguous C:/Boost/include/boost-1_38/boost/bind/mem_fn_cc.hpp:15: note: candidates are: boost::_mfi::mf0<R, T> boost::mem_fn(R (T::*)()) [with R = ULONG, T = IDirect3DDevice9] C:/Boost/include/boost-1_38/boost/bind/mem_fn_cc.hpp:15: note: boost::_mfi::mf0_stdcall<R, T> boost::mem_fn(R (T::*)()) [with R = ULONG, T = IDirect3DDevice9] C:/Boost/include/boost-1_38/boost/mem_fn.hpp:382: note: boost::_mfi::dm<R, T> boost::mem_fn(R T::*) [with R = ULONG ()(), T = IDirect3DDevice9] Many thanks, Conrad