Eric Fiselier 6be02cb83f Fix race conditions in test class used throughout the std::thread tests.
The test class 'G' reads and writes to the same static variables in its
constructor, destructor and call operator. When threads are
constructed using `std::thread t((G()))` there is a race condition between the
destruction of the temporary and the execution of `G::operator()()`.

The fix is to simply create the input before creating the thread.


git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@233946 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-02 21:12:17 +00:00

55 lines
1.0 KiB
C++

//===----------------------------------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// UNSUPPORTED: libcpp-has-no-threads
// <thread>
// class thread
// void join();
#include <thread>
#include <new>
#include <cstdlib>
#include <cassert>
class G
{
int alive_;
public:
static int n_alive;
static bool op_run;
G() : alive_(1) {++n_alive;}
G(const G& g) : alive_(g.alive_) {++n_alive;}
~G() {alive_ = 0; --n_alive;}
void operator()()
{
assert(alive_ == 1);
assert(n_alive >= 1);
op_run = true;
}
};
int G::n_alive = 0;
bool G::op_run = false;
int main()
{
{
G g;
std::thread t0(g);
assert(t0.joinable());
t0.join();
assert(!t0.joinable());
}
}