Hi - I am trying to recompile code that compiles cleanly with g++ 3.0.4 with g++ 3.1. I get the following error messages, which, I am affraid, I cannot decipher. Any hints would be greatly appreciated. -Francois g++ -c -g -fPIC -DBOOST -I/usr/local/ap/include/python2.2 -I/usr/local/ap/PLplot/include -I/usr/local/ap/galib/include -o pymathlib.o pymathlib.cc/usr/local/ap/include/boost/python/cross_module.hpp: In instantiation of `SuperCode::Vector<Real>& boost::python::from_python(PyObject*, boost::python::type, bool)': /usr/local/ap/include/boost/python/caller.hpp:1093: instantiated from `static PyObject* boost::python::caller<void>::call(void (*)(A1, A2, A3), PyObject*, PyObject*) [with A1 = SuperCode::Vector<Real>&, A2 = const SuperCode::Vector<Real>&, A3 = const SuperCode::Vector<Real>&]' /usr/local/ap/include/boost/python/detail/functions.hpp:73: instantiated from `PyObject* boost::python::detail::wrapped_function_pointer::do_call(PyObject*, PyObject*) const [with R = Void, F = Void (*)(SuperCode::Vector<Real>&, const SuperCode::Vector<Real>&, const SuperCode::Vector<Real>&)]' /usr/local/ap/include/boost/function/function_base.hpp:153: instantiated from here /usr/local/ap/include/boost/python/cross_module.hpp:91: default argument given for parameter 3 of `SuperCode::Vector<Real>& boost::python::from_python(PyObject*, boost::python::type, bool = false)' /usr/local/ap/include/boost/python/cross_module.hpp:91: after previous specification in `SuperCode::Vector<Real>& boost::python::from_python(PyObject*, boost::python::type, bool = false)' /usr/local/ap/include/boost/python/cross_module.hpp: In instantiation of `const SuperCode::Vector<Real>& boost::python::from_python(PyObject*, boost::python::type, bool)': /usr/local/ap/include/boost/python/caller.hpp:1093: instantiated from `static PyObject* boost::python::caller<void>::call(void (*)(A1, A2, A3), PyObject*, PyObject*) [with A1 = SuperCode::Vector<Real>&, A2 = const SuperCode::Vector<Real>&, A3 = const SuperCode::Vector<Real>&]' /usr/local/ap/include/boost/python/detail/functions.hpp:73: instantiated from `PyObject* boost::python::detail::wrapped_function_pointer::do_call(PyObject*, PyObject*) const [with R = Void, F = Void (*)(SuperCode::Vector<Real>&, const SuperCode::Vector<Real>&, const SuperCode::Vector<Real>&)]' /usr/local/ap/include/boost/function/function_base.hpp:153: instantiated from here /usr/local/ap/include/boost/python/cross_module.hpp:94: default argument given for parameter 3 of `const SuperCode::Vector<Real>& boost::python::from_python(PyObject*, boost::python::type, bool = false)' /usr/local/ap/include/boost/python/cross_module.hpp:94: after previous specification in `const SuperCode::Vector<Real>& boost::python::from_python(PyObject*, boost::python::type, bool = false)'