1 // RUN: %clang_cc1 -fsyntax-only -std=c++11 %s 2 3 template <class T> 4 T&& 5 declval() noexcept; 6 7 template <class T> 8 struct some_trait 9 { 10 static const bool value = false; 11 }; 12 13 template <class T> swap(T & x,T & y)14void swap(T& x, T& y) noexcept(some_trait<T>::value) 15 { 16 T tmp(static_cast<T&&>(x)); 17 x = static_cast<T&&>(y); 18 y = static_cast<T&&>(tmp); 19 } 20 21 template <class T, unsigned N> 22 struct array 23 { 24 T data[N]; 25 26 void swap(array& a) noexcept(noexcept(::swap(declval<T&>(), declval<T&>()))); 27 }; 28 29 struct DefaultOnly 30 { 31 DefaultOnly() = default; 32 DefaultOnly(const DefaultOnly&) = delete; 33 DefaultOnly& operator=(const DefaultOnly&) = delete; 34 ~DefaultOnly() = default; 35 }; 36 main()37int main() 38 { 39 array<DefaultOnly, 1> a, b; 40 } 41 42