clang/test/Parser/cxx-template-template-recovery.cpp

   1 // RUN: %clang_cc1 -std=c++20 -verify -fsyntax-only %s
   2
   3 namespace a {
   4   template <typename T>
   5   concept C1 = true; // #C1
   6
   7   template <typename T>
   8   auto V1 = true; // #V1
   9
  10   namespace b {
  11     template <typename T>
  12     concept C2 = true; // #C2
  13     template <typename T>
  14     auto V2 = true; // #V2
  15   }
  16 }
  17
  18 template <typename T>
  19 concept C3 = true; // #C3
  20 template <typename T>
  21 auto V3 = true; // #V3
  22 template <template <typename T> typename C>
  23 constexpr bool test = true;
  24
  25 static_assert(test<a::C1>); // expected-error {{too few template arguments for concept 'C1'}} \
  26                             // expected-note@#C1 {{here}}
  27 static_assert(test<a::b::C2>); // expected-error {{too few template arguments for concept 'C2'}} \
  28                                // expected-note@#C2 {{here}}
  29 static_assert(test<C3>); // expected-error {{too few template arguments for concept 'C3'}} \
  30                          // expected-note@#C3 {{here}}
  31
  32 static_assert(test<a::V1>); // expected-error {{use of variable template 'V1' requires template arguments}} \
  33                             // expected-note@#V1 {{here}}
  34 static_assert(test<a::b::V2>); // expected-error {{use of variable template 'V2' requires template arguments}} \
  35                             // expected-note@#V2 {{here}}
  36 static_assert(test<V3>); // expected-error {{use of variable template 'V3' requires template arguments}} \
  37                          // expected-note@#V3 {{here}}
  38
  39
  40 void f() {
  41     C3 t1 = 0;  // expected-error {{expected 'auto' or 'decltype(auto)' after concept name}}
  42     a::C1 t2 = 0; // expected-error {{expected 'auto' or 'decltype(auto)' after concept name}}
  43     a::b::C2 t3 = 0; // expected-error {{expected 'auto' or 'decltype(auto)' after concept name}}
  44 }