gcc/testsuite/g++.dg/cpp0x/sfinae33.C

// PR c++/52422
// { dg-options -std=c++11 }

template<class T>
struct add_rval_ref
{
  typedef T&& type;
};

template<>
struct add_rval_ref<void>
{
  typedef void type;
};

template<class T>
typename add_rval_ref<T>::type create();

template<class T, 
  class = decltype(create<T>()())
>
auto f(int) -> char(&)[1];

template<class>
auto f(...) -> char(&)[2];

static_assert(sizeof(f<void>(0)) != 1, "");