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 11 12 // There's currently no release of OS X whose dylib contains the patch for 13 // PR38682. Since the fix for future<void> is in the dylib, this test may fail. 14 // UNSUPPORTED: use_system_cxx_lib && target={{.+}}-apple-macosx10.{{9|10|11|12|13|14}} 15 16 // This test is designed to cause and allow TSAN to detect a race condition 17 // in std::async, as reported in https://llvm.org/PR38682. 18 19 #include <cassert> 20 #include <functional> 21 #include <future> 22 #include <numeric> 23 #include <vector> 24 25 #include "test_macros.h" 26 27 28 static int worker(std::vector<int> const& data) { 29 return std::accumulate(data.begin(), data.end(), 0); 30 } 31 32 static int& worker_ref(int& i) { return i; } 33 34 static void worker_void() { } 35 36 int main(int, char**) { 37 // future<T> 38 { 39 std::vector<int> const v{1, 2, 3, 4, 5, 6, 7, 8, 9, 10}; 40 for (int i = 0; i != 20; ++i) { 41 std::future<int> fut = std::async(std::launch::async, worker, v); 42 int answer = fut.get(); 43 assert(answer == 55); 44 } 45 } 46 47 // future<T&> 48 { 49 for (int i = 0; i != 20; ++i) { 50 std::future<int&> fut = std::async(std::launch::async, worker_ref, std::ref(i)); 51 int& answer = fut.get(); 52 assert(answer == i); 53 } 54 } 55 56 // future<void> 57 { 58 for (int i = 0; i != 20; ++i) { 59 std::future<void> fut = std::async(std::launch::async, worker_void); 60 fut.get(); 61 } 62 } 63 64 return 0; 65 } 66