listing_5.9.cpp

#include <atomic>
#include <thread>
#include <assert.h>

std::atomic<int> data[5];
std::atomic<bool> sync1(false),sync2(false);

void thread_1()
{
    data[0].store(42,std::memory_order_relaxed);
    data[1].store(97,std::memory_order_relaxed);
    data[2].store(17,std::memory_order_relaxed);
    data[3].store(-141,std::memory_order_relaxed);
    data[4].store(2003,std::memory_order_relaxed);
    sync1.store(true,std::memory_order_release);
}

void thread_2()
{
    while(!sync1.load(std::memory_order_acquire));
    sync2.store(std::memory_order_release);
}

void thread_3()
{
    while(!sync2.load(std::memory_order_acquire));
    assert(data[0].load(std::memory_order_relaxed)==42);
    assert(data[1].load(std::memory_order_relaxed)==97);
    assert(data[2].load(std::memory_order_relaxed)==17);
    assert(data[3].load(std::memory_order_relaxed)==-141);
    assert(data[4].load(std::memory_order_relaxed)==2003);
}

int main()
{
    std::thread t1(thread_1);
    std::thread t2(thread_2);
    std::thread t3(thread_3);
    t1.join();
    t2.join();
    t3.join();
}