http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48113
Jonathan Wakely <redi at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |jason at gcc dot gnu.org --- Comment #3 from Jonathan Wakely <redi at gcc dot gnu.org> 2011-03-14 16:22:44 UTC --- Jason, could you take a look at this reduced testcase, which has no libstdc++ dependency? template<typename T> T declval(); struct tuple { }; struct F1 { void operator()(tuple); }; typedef void (*F2)(tuple); template<typename F, typename T> struct Bind { decltype( F()(declval<T&>()) ) f(); decltype( F()(declval<volatile T&>()) ) f() volatile; }; int main() { Bind<F1, tuple>().f(); // OK Bind<F2, tuple>().f(); // ERROR } This shows that SFINAE removes the Bind::f() volatile overload if F is a functor, but not if it's a function pointer. I can't see why it should be different. Is this a FE bug, or do I need to handle function pointers differently in std::bind? Thanks