libcxx/test/std/thread/thread.jthread/hardware_concurrency.pass.cpp

   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: no-threads
  10 // UNSUPPORTED: c++03, c++11, c++14, c++17
  11 // XFAIL: availability-synchronization_library-missing
  12
  13 // [[nodiscard]] static unsigned int hardware_concurrency() noexcept;
  14
  15 #include <cassert>
  16 #include <concepts>
  17 #include <thread>
  18 #include <type_traits>
  19
  20 #include "test_macros.h"
  21
  22 static_assert(noexcept(std::jthread::hardware_concurrency()));
  23
  24 int main(int, char**) {
  25   std::same_as<unsigned int> decltype(auto) result = std::jthread::hardware_concurrency();
  26   assert(result == std::thread::hardware_concurrency());
  27
  28   return 0;
  29 }