clang/test/SemaCXX/PR62533.cpp

   1 // RUN: %clang_cc1 -fsyntax-only -verify %s
   2
   3 template<typename T>
   4 struct test {
   5   template<typename> using fun_diff = char; // expected-note 2{{type alias template declared here}}
   6 };
   7
   8 template<typename T, typename V>
   9 decltype(T::template fun_diff<V>) foo1() {}
  10 // expected-note@-1 {{candidate template ignored: substitution failure [with T = test<int>, V = int]: 'test<int>::fun_diff' is expected to be a non-type template, but instantiated to a type alias template}}
  11
  12 template<typename T>
  13 void foo2() {
  14   // expected-error@+1 {{test<int>::fun_diff' is expected to be a non-type template, but instantiated to a type alias template}}
  15   int a = test<T>::template fun_diff<int>;
  16 }
  17
  18 template<typename T, typename V>
  19 struct has_fun_diff {
  20   using type = double;
  21 };
  22
  23 template<typename T>
  24 struct has_fun_diff<T, int> {
  25   // expected-error@+1 {{'test<int>::fun_diff' is expected to be a non-type template, but instantiated to a type alias template}}
  26   using type = decltype(T::template fun_diff<int>);
  27 };
  28
  29 void bar() {
  30   foo1<test<int>, int>(); // expected-error {{no matching function for call to 'foo1'}}
  31   foo2<int>(); // expected-note {{in instantiation of function template specialization}}
  32   has_fun_diff<test<int>, int>::type a; // expected-note {{in instantiation of template class}}
  33 }