Files
clang-p2996/libcxx/test/std/thread/futures/futures.async/async_race.38682.pass.cpp
Louis Dionne ed61d6a466 [libc++] Use the stdlib=<LIB> Lit feature instead of use_system_cxx_lib
The use_system_cxx_lib Lit feature was only used for back-deployment
testing. However, one immense hole in that setup was that we didn't
have a proper way to test Apple's own libc++ outside of back-deployment,
which was embodied by the fact that we needed to define _LIBCPP_DISABLE_AVAILABILITY
when testing (see change in libcxx/utils/libcxx/test/params.py).

This led to the apple-system testing configuration not checking for
availability markup, which is obviously quite bad since the library
we ship actually has availability markup.

Using stdlib=<VENDOR>-libc++ instead to encode back-deployment restrictions
on tests is simpler and it makes it possible to naturally support tests
such as availability markup checking even in the tip-of-trunk Apple-libc++
configuration.

Differential Revision: https://reviews.llvm.org/D146366
2023-03-30 06:57:56 -04:00

66 lines
1.7 KiB
C++

//===----------------------------------------------------------------------===//
//
// 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: 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: stdlib=apple-libc++ && 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;
}