clang/test/CXX/drs/cwg2335.cpp

   1 // RUN: %clang_cc1 -std=c++98 %s -verify=expected -fexceptions -fcxx-exceptions -pedantic-errors
   2 // RUN: %clang_cc1 -std=c++11 %s -verify=expected -fexceptions -fcxx-exceptions -pedantic-errors
   3 // RUN: %clang_cc1 -std=c++14 %s -verify=expected,since-cxx14 -fexceptions -fcxx-exceptions -pedantic-errors
   4 // RUN: %clang_cc1 -std=c++17 %s -verify=expected,since-cxx14 -fexceptions -fcxx-exceptions -pedantic-errors
   5 // RUN: %clang_cc1 -std=c++20 %s -verify=expected,since-cxx14 -fexceptions -fcxx-exceptions -pedantic-errors
   6 // RUN: %clang_cc1 -std=c++23 %s -verify=expected,since-cxx14 -fexceptions -fcxx-exceptions -pedantic-errors
   7 // RUN: %clang_cc1 -std=c++2c %s -verify=expected,since-cxx14 -fexceptions -fcxx-exceptions -pedantic-errors
   8
   9 #if __cplusplus <= 201103L
  10 // expected-no-diagnostics
  11 #endif
  12
  13 namespace cwg2335 { // cwg2335: no drafting 2018-06
  14 // FIXME: current consensus is that the examples are well-formed.
  15 #if __cplusplus >= 201402L
  16 namespace ex1 {
  17 template <class...> struct partition_indices {
  18   static auto compute_right() {}
  19   static constexpr auto right = compute_right;
  20 };
  21 template struct partition_indices<int>;
  22 } // namespace ex1
  23
  24 namespace ex2 {
  25 template <int> struct X {};
  26 template <class T> struct partition_indices {
  27   static auto compute_right() { return X<I>(); }
  28   // since-cxx14-error@-1 {{no member 'I' in 'cwg2335::ex2::partition_indices<int>'; it has not yet been instantiated}}
  29   //   since-cxx14-note@#cwg2335-ex2-right {{in instantiation of member function 'cwg2335::ex2::partition_indices<int>::compute_right' requested here}}
  30   //   since-cxx14-note@#cwg2335-ex2-inst {{in instantiation of template class 'cwg2335::ex2::partition_indices<int>' requested here}}
  31   //   since-cxx14-note@#cwg2335-ex2-I {{not-yet-instantiated member is declared here}}
  32   static constexpr auto right = compute_right; // #cwg2335-ex2-right
  33   static constexpr int I = sizeof(T); // #cwg2335-ex2-I
  34 };
  35 template struct partition_indices<int>; // #cwg2335-ex2-inst
  36 } // namespace ex2
  37
  38 namespace ex3 {
  39 struct partition_indices {
  40   static auto compute_right() {} // #cwg2335-compute_right
  41   static constexpr auto right = compute_right; // #cwg2335-ex3-right
  42   // since-cxx14-error@-1 {{function 'compute_right' with deduced return type cannot be used before it is defined}}
  43   //   since-cxx14-note@#cwg2335-compute_right {{'compute_right' declared here}}
  44   // since-cxx14-error@#cwg2335-ex3-right {{declaration of variable 'right' with deduced type 'const auto' requires an initializer}}
  45 };
  46 } // namespace ex3
  47 #endif
  48 } // namespace cwg2335