Hello, I got an error from the Sun Studio 12.2 (CC 5.11) when trying to compile my sources. The error comes out of the Boost.Proto library (actually I'm doing something with Boost.Spirit and Boost.Spirit is using Boost.Proto ..., but I don't think that the problem is in the client code, it seems to come from the buggy compiler). I'm using Boost 1.43. This is what I got from the compiler: "...include/boost/proto/detail/decltype.hpp", line 343: Error: Partial specialization parameter V is not used in the arguments. "...include/boost/proto/transform/arg.hpp", line 287: Error: Partial specialization for boost::proto::_byval::result has identical arguments. "...include/boost/proto/extends.hpp", line 600: Error: type is not a member of boost::result_of<boost::proto::domainns_::default_domain>. "...include/boost/spirit/home/support/terminal.hpp", line 237: Where: While specializing "boost::proto::exprns_::extends<boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::term<boost::spirit::tag::bin>, 0>, boost::spirit::terminal<boost::spirit::tag::bin>, boost::proto::domainns_::default_domain, 0>". (the following is talking about "include/boost/proto/detail/decltype.hpp", line 343) With g++ this code compiles without any problems and runs as expected. Searching around the internet, I got the following bug entry of the Sun Studio compiler: http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=6926895 It looks like a similar problem. The bug entry contains a small example which reproduces the compile error: template <typename T> struct test { T t; }; template <typename T, typename X> struct test<X T::*> { X T::* x; }; template <typename T> struct test2 {}; template <typename T, typename X> struct test2< test<X T::*> > { test<X T::*> xt; }; int main() { test<int> a; a.t = 1; int test<int>::* s = &test<int>::t; test<int test<int>::*> a2; a2.x = s; test2<test<int test<int>::* > > a3; a3.xt = a2; return a.*a3.xt.x; } $ CC example.C "example.C", line 4: Error: Partial specialization parameter T is not used in the arguments. The bug entry also provides a workaround which seems to work. Replace the template types with the following: template <typename T> struct helper { }; template <typename T> struct test2 : public test2< helper<T> > { }; template <typename T> struct test2<helper< T> > { } ; template <typename T, typename X > struct test2< helper<test<X T::* > > {test<X T::*> xt; }; I would like to try a similar workaround adapted to the Boost.Proto source code. I tried several things but since I'm not fully aware what is going on in the proto sources and what is the exact reason the compiler fails, I couldn't make it work so far. Does anybody had a similar problem or does anybody know how to adapt the Boost.Proto source to make the Sun compiler happy? BTW: For me it would be ok for now to patch my local Boost source files. Here is the snippet from proto/detail/decltype.hpp: //////////////////////////////////////////////////////////////////////////////////////////// // result_of_ is a wrapper around boost::result_of that also handles "invocations" of // member object pointers. template<typename T, typename Void = void> struct result_of_ : boost::result_of<T> {}; // THE FOLLOWING IS TROUBLE MAKER FOR THE SUN COMPILER -> template<typename T, typename U, typename V> struct result_of_<T U::*(V), typename enable_if_c<is_member_object_pointer<T U::*>::value>::type> { BOOST_STATIC_CONSTANT(bool, is_V_a_smart_ptr = 2 == sizeof(test_V_is_a_U<U>(&lvalue(make<V>())))); BOOST_STATIC_CONSTANT(bool, is_ptr_to_const = 2 == sizeof(test_ptr_to_const(BOOST_PROTO_GET_POINTER(U, make<V>())))); // If V is not a U, then it is a (smart) pointer and we can always return an lvalue. // Otherwise, we can only return an lvalue if we are given one. typedef typename mpl::eval_if_c< (is_V_a_smart_ptr || is_reference<V>::value) , mpl::eval_if_c< is_ptr_to_const , add_reference<typename add_const<T>::type> , add_reference<T> > , mpl::identity<T> >::type type; }; Thanks in advance, Sascha