1 //===----------------------------------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 // UNSUPPORTED: c++03, c++11, c++14, c++17
10 
11 // template<class T>
12 // concept bidirectional_iterator;
13 
14 #include <iterator>
15 
16 #include <concepts>
17 
18 template<std::forward_iterator I>
check_subsumption()19 constexpr bool check_subsumption() {
20   return false;
21 }
22 
23 template<std::bidirectional_iterator>
check_subsumption()24 constexpr bool check_subsumption() {
25   return true;
26 }
27 
28 static_assert(check_subsumption<int*>());
29