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//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// UNSUPPORTED: libcpp-has-no-threads
// UNSUPPORTED: c++03
// There's currently no release of OS X whose dylib contains the patch for
// PR38682. Since the fix for future<void> is in the dylib, this test may fail.
// UNSUPPORTED: use_system_cxx_lib && target={{.+}}-apple-macosx10.{{9|10|11|12|13|14}}
// This test is designed to cause and allow TSAN to detect a race condition
// in std::async, as reported in https://llvm.org/PR38682.
#include <cassert>
#include <functional>
#include <future>
#include <numeric>
#include <vector>
#include "test_macros.h"
static int worker(std::vector<int> const& data) {
return std::accumulate(data.begin(), data.end(), 0);
}
static int& worker_ref(int& i) { return i; }
static void worker_void() { }
int main(int, char**) {
// future<T>
{
std::vector<int> const v{1, 2, 3, 4, 5, 6, 7, 8, 9, 10};
for (int i = 0; i != 20; ++i) {
std::future<int> fut = std::async(std::launch::async, worker, v);
int answer = fut.get();
assert(answer == 55);
}
}
// future<T&>
{
for (int i = 0; i != 20; ++i) {
std::future<int&> fut = std::async(std::launch::async, worker_ref, std::ref(i));
int& answer = fut.get();
assert(answer == i);
}
}
// future<void>
{
for (int i = 0; i != 20; ++i) {
std::future<void> fut = std::async(std::launch::async, worker_void);
fut.get();
}
}
return 0;
}
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