libcxx/test/std/thread/thread.jthread/nodiscard.verify.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]] bool joinable() const noexcept;
  14 // [[nodiscard]] id get_id() const noexcept;
  15 // [[nodiscard]] native_handle_type native_handle();
  16 // [[nodiscard]] stop_source get_stop_source() noexcept;
  17 // [[nodiscard]] stop_token get_stop_token() const noexcept;
  18 // [[nodiscard]] static unsigned int hardware_concurrency() noexcept;
  19
  20 #include <thread>
  21
  22 void test() {
  23   std::jthread jt;
  24   jt.joinable();             // expected-warning {{ignoring return value of function}}
  25   jt.get_id();               // expected-warning {{ignoring return value of function}}
  26   jt.native_handle();        // expected-warning {{ignoring return value of function}}
  27   jt.get_stop_source();      // expected-warning {{ignoring return value of function}}
  28   jt.get_stop_token();       // expected-warning {{ignoring return value of function}}
  29   jt.hardware_concurrency(); // expected-warning {{ignoring return value of function}}
  30 }