Hi, Possibly related but old: https://mail.python.org/pipermail/cplusplus-sig/2005-October/009304.html Trying to create a boost::python::object with an instance of a class that has a "crazy" operator& fails here: boost/python/converter/arg_to_python.hpp:209:9: error: no matching constructor for initialization of 'boost::python::converter::detail::arg_to_python_base' : arg_to_python_base(&x, registered<T>::converters) Replacing "&x" with "addressof(x)" solve the issue, if you don't see any drawback I suggest it could be changed in the next release :) Note: I know that overloading wildy the operator& is considered as bad, but my sample code seems quite "standard": std::vector<bool> v { true }; boost::python::object b_(v[0]); It fails when compiling with libc++ as they handle (the infamous) std::vector<bool> in a (non standard) way similar as std::bitset and provided a class to wrap reference to element of the vector. This __bit_reference overloads the operator& to return a __bit_iterator, which breaks boost::python::object initialization. The trace is: include/boost/python/converter/arg_to_python.hpp:256:7: note: in instantiation of member function 'boost::python::converter::detail::value_arg_to_python<std::__1::__bit_reference<std::__1::vector<bool, std::__1::allocator<bool> >, true> >::value_arg_to_python' requested here : base(x) ^ include/boost/python/object_core.hpp:393:33: note: in instantiation of member function 'boost::python::converter::arg_to_python<std::__1::__bit_reference<std::__1::vector<bool, std::__1::allocator<bool> >, true> >::arg_to_python' requested here return python::incref(converter::arg_to_python<T>(x).get()); ^ include/boost/python/object_core.hpp:312:10: note: in instantiation of function template specialization 'boost::python::api::object_initializer_impl<false, false>::get<std::__1::__bit_reference<std::__1::vector<bool, std::__1::allocator<bool> >, true> >' requested here >::get( ^ include/boost/python/object_core.hpp:334:23: note: in instantiation of function template specialization 'boost::python::api::object_base_initializer<std::__1::__bit_reference<std::__1::vector<bool, std::__1::allocator<bool> >, true> >' requested here : object_base(object_base_initializer(x)) ^ helloworld.cpp:28:25: note: in instantiation of function template specialization 'boost::python::api::object::object<std::__1::__bit_reference<std::__1::vector<bool, std::__1::allocator<bool> >, true> >' requested here boost::python::object b_(v[0]); ^ include/boost/python/converter/arg_to_python_base.hpp:20:7: note: candidate constructor not viable: no known conversion from '__bit_iterator<std::__1::vector<bool, std::__1::allocator<bool> >, false>' to 'const volatile void *' for 1st argument arg_to_python_base(void const volatile* source, registration const&); ^ Best, Mehdi