Files
clang-p2996/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.guard/std.mutex.pass.cpp
Petr Hosek 6192f458f4 [libc++] Make std::lock_guard available with _LIBCPP_HAS_NO_THREADS (#98717)
This change makes `std::lock_guard` available when
`_LIBCPP_HAS_NO_THREADS` is set. This class is generic and doesn't
require threading support, and is regularly used even in environments
where threading isn't available like embedded.

fixes #89891

---------

Co-authored-by: Louis Dionne <ldionne.2@gmail.com>
2024-07-16 21:58:13 -07:00

50 lines
1.2 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
// Test the interoperation of std::lock_guard with std::mutex, since that is such
// a common use case.
#include <cassert>
#include <mutex>
#include <type_traits>
#include <functional>
#include "make_test_thread.h"
#include "test_macros.h"
void do_try_lock(std::mutex& m) { assert(m.try_lock() == false); }
int main(int, char**) {
{
std::mutex m;
{
std::lock_guard<std::mutex> lg(m);
std::thread t = support::make_test_thread(do_try_lock, std::ref(m));
t.join();
}
// This should work because the lock_guard unlocked the mutex when it was destroyed above.
m.lock();
m.unlock();
}
// Test CTAD
#if TEST_STD_VER >= 17
{
std::mutex m;
std::lock_guard lg(m);
static_assert(std::is_same<decltype(lg), std::lock_guard<std::mutex>>::value, "");
}
#endif
return 0;
}