clang/test/SemaCXX/decltype-overloaded-functions.cpp

   1 // RUN: %clang_cc1 -fsyntax-only -verify %s -std=c++11
   2
   3 void f();  // expected-note{{possible target for call}}
   4 void f(int);  // expected-note{{possible target for call}}
   5 decltype(f) a;  // expected-error{{reference to overloaded function could not be resolved; did you mean to call it with no arguments?}} expected-error {{variable has incomplete type 'decltype(f())' (aka 'void')}}
   6
   7 template<typename T> struct S {
   8   decltype(T::f) * f; // expected-error {{call to non-static member function without an object argument}}
   9 };
  10
  11 struct K {
  12   void f();
  13   void f(int);
  14 };
  15 S<K> b; // expected-note{{in instantiation of template class 'S<K>' requested here}}
  16
  17 namespace PR13978 {
  18   template<typename T> struct S { decltype(1) f(); };
  19   template<typename T> decltype(1) S<T>::f() { return 1; }
  20
  21   // This case is ill-formed (no diagnostic required) because the decltype
  22   // expressions are functionally equivalent but not equivalent. It would
  23   // be acceptable for us to reject this case.
  24   template<typename T> struct U { struct A {}; decltype(A{}) f(); };
  25   template<typename T> decltype(typename U<T>::A{}) U<T>::f() {}
  26
  27   // This case is valid.
  28   template<typename T> struct V { struct A {}; decltype(typename V<T>::A{}) f(); };
  29   template<typename T> decltype(typename V<T>::A{}) V<T>::f() {}
  30 }