我試圖編譯C++原子的基本示例&線程雖然當我編譯main.cpp文件gcc拋出一些std lib錯誤 - 這似乎無關我的代碼。GCC標誌爲C++ 0x原子和線程
的main.cpp
#include <thread>
#include <atomic>
#include <stdio.h>
#include "randomdelay.h"
using namespace std;
atomic<int> flag;
int sharedValue = 0;
RandomDelay randomDelay1(1, 60101);
RandomDelay randomDelay2(2, 65535);
void IncrementSharedValue10000000Times(RandomDelay& randomDelay)
{
int count = 0;
while (count < 10000000)
{
randomDelay.doBusyWork();
int expected = 0;
if (flag.compare_exchange_strong(expected, 1, memory_order_relaxed))
{
// Lock was successful
sharedValue++;
flag.store(0, memory_order_relaxed);
count++;
}
}
}
void Thread2Func()
{
IncrementSharedValue10000000Times(randomDelay2);
}
int main(int argc, char* argv[])
{
printf("is_lock_free: %s\n", flag.is_lock_free() ? "true" : "false");
for (;;) {
sharedValue = 0;
thread thread2(Thread2Func);
IncrementSharedValue10000000Times(randomDelay1);
thread2.join();
printf("sharedValue=%d\n", sharedValue);
}
return 0;
}
我使用的是全碼:https://github.com/preshing/AcquireRelease
這裏的海灣合作委員會的錯誤消息:
[[email protected] preshing-AcquireRelease-1422872]$ g++ -std=c++0x -pthread main.cpp
/tmp/cc95LElq.o: In function `IncrementSharedValue10000000Times(RandomDelay&)':
main.cpp:(.text+0xdd): undefined reference to `RandomDelay::doBusyWork()'
/tmp/cc95LElq.o: In function `__static_initialization_and_destruction_0(int, int)':
main.cpp:(.text+0x23d): undefined reference to `RandomDelay::RandomDelay(int, int)'
main.cpp:(.text+0x251): undefined reference to `RandomDelay::RandomDelay(int, int)'
collect2: error: ld returned 1 exit status
下面是我用命令:g++ -std=c++0x -pthread main.cpp
如何在這些不相關的代碼?未定義對'RandomDelay'中所有函數的引用。 – GManNickG
@GManNickG我指的是GCC標誌。 – TheBlueCat
是什麼導致你設置這個關於原子和GCC標誌的問題? –