According to http://ift.tt/1EOXRfI
Magic statics (http://ift.tt/1zyMJxb) are supported on VS2015
However testing the following code in debug x64 Vs2015 Update 3
#include "stdafx.h"
#include <iostream>
#include <windows.h>
#include <tchar.h>
#define MAX_THREADS 5
class Sleeper
{
public:
Sleeper()
{
std::cout << "Sleeper \n";
Sleep(100000);
}
};
DWORD WINAPI MyThreadFunction(LPVOID lpParam)
{
std::cout << "Sleeper Start" << (int)lpParam << "\n";
static Sleeper s;
std::cout << "Sleeper Done" << (int)lpParam << "\n";
return 0;
}
int main(int, char**)
{
DWORD dwThreadIdArray[MAX_THREADS];
HANDLE hThreadArray[MAX_THREADS];
// Create MAX_THREADS worker threads.
for (int i = 0; i<MAX_THREADS; i++)
{
// Create the thread to begin execution on its own.
hThreadArray[i] = CreateThread(
NULL, // default security attributes
0, // use default stack size
MyThreadFunction, // thread function name
(LPVOID)i, // argument to thread function
0, // use default creation flags
&dwThreadIdArray[i]); // returns the thread identifier
// Check the return value for success.
// If CreateThread fails, terminate execution.
// This will automatically clean up threads and memory.
if (hThreadArray[i] == NULL)
{
ExitProcess(3);
}
} // End of main thread creation loop.
// Wait until all threads have terminated.
WaitForMultipleObjects(MAX_THREADS, hThreadArray, TRUE, INFINITE);
// Close all thread handles and free memory allocations.
for (int i = 0; i<MAX_THREADS; i++)
{
CloseHandle(hThreadArray[i]);
}
return 0;
}
gives output
Sleeper Start0 Sleeper Sleeper Start2 Sleeper Start3 Sleeper Start1 Sleeper Start4
Which indicates that initializing static variable s is actually not thread safe.
Aucun commentaire:
Enregistrer un commentaire