调试断言失败:下标超出 std::vector 的范围

我正在尝试解决此问题，这似乎我正在以超出范围的索引访问，但是VS无法在发生错误的地方停止，这使我对导致此问题的原因感到困惑。

错误：

调试断言失败！程序：。。。。文件：c：\program files\Microsoft Visual Studio 10.0\vc\include\vector 行：1440 表达式：字符串下标超出范围

该程序的作用：

有两个线程：

线程 1：

第一个线程使用 GetForegroundWindow() 查找（除其他事项外）当前窗口中的更改，检查不是在循环中发生，而是在触发WH_MOUSE_LL事件时发生。数据被拆分为固定大小的结构，以便可以通过 tcp 发送到服务器。第一个线程，并将数据（窗口标题）记录到当前结构中的std::list中。

if(change_in_window)
{
    GetWindowTextW(hActWin,wTitle,256);
    std::wstring title(wTitle);
    current_struct->titles.push_back(title);
}

线程 2：

第二个线程称为查找尚未发送的结构，它将其内容放入char缓冲区中，以便可以通过 tcp 发送它们。虽然我不知道错误到底在哪里，但从字符串或列表的错误类型来看，这是我整个应用程序中唯一使用列表/字符串的代码（其余的是常规数组）。此外，如代码注释中所述注释 if 块可阻止错误发生。

  BOOL SendStruct(DATABLOCK data_block,bool sycn)
    {
    [..]
                int _size = 0;
// Important note, when this if block is commented the error ceases to exist, so it has something to do with the following block
                if(!data_block.titles.empty()) //check if std::list is empty
                {
                    for (std::list<std::wstring>::iterator itr  = data_block.titles.begin(); itr != data_block.titles.end() ; itr++) {
                        _size += (((*itr).size()+1) * 2); 
                    } //calculate size required. Note the +1 is for an extra character between every title
                    wchar_t* wnd_wbuffer = new wchar_t[_size/2](); //allocate space
                    int _last = 0;
    //loop through every string and every char of a string and write them down
                    for (std::list<std::wstring>::iterator itr = data_block.titles.begin(); itr != data_block.titles.end(); itr++)
                    {
                        for(unsigned int i = 0; i <= (itr->size()-1); i++)
                        {
                            wnd_wbuffer[i+_last] = (*itr)[i] ;
                        }
                        wnd_wbuffer[_last+itr->size()] = 0x00A6; // separator
                        _last += itr->size()+1;
                    }
                    unsigned char* wnd_buffer = new unsigned char[_size];
                    wnd_buffer = (unsigned char*)wnd_wbuffer;
                    h_io->header_w_size = _size;
                    h_io->header_io_wnd = 1;
                    Connect(mode,*header,conn,buffer_in_bytes,wnd_buffer,_size);
                    delete wnd_wbuffer;
                }
                else
            [..]
                return true;
            }

我的线程同步尝试：有一个指向创建的第一个data_block的指针 （db_main）指向当前data_block的指针 （db_cur）

//datablock format
    typedef struct _DATABLOCK
        {
            [..]
            int logs[512];
            std::list<std::wstring> titles;
            bool bPrsd; // has this datablock been sent true/false
            bool bFull; // is logs[512] full true/false
            [..]
            struct _DATABLOCK *next;
        } DATABLOCK;    

//This is what thread 1 does when it needs to register a mouse press and it is called like this:
    if(change_in_window)
    {
        GetWindowTextW(hActWin,wTitle,256);
        std::wstring title(wTitle);
        current_struct->titles.push_back(title);
    }
    RegisterMousePress(args);
    [..]
//pseudo-code to simplify things , although original function does the exact same thing. 
    RegisterMousePress()
        {
            if(it_is_full)
            {
                db_cur->bFull= true;
                if(does db_main exist)
                {
                    db_main = new DATABLOCK;
                    db_main = db_cur;
                    db_main->next = NULL;
                }
                else
                {
                    db_cur->next = new DATABLOCK;
                    db_cur = db_cur->next;
                    db_cur->next = NULL;
                }
                SetEvent(eProcessed); //tell thread 2 there is at least one datablock ready
            }
            else
            {
            write_to_it();
            }
        }
//this is actual code and entry point of thread 2 and my attempy at synchronization
    DWORD WINAPI InitQueueThread(void* Param)
    {
        DWORD rc;
        DATABLOCK* k;
        SockWClient writer;
        k = db_main;
        while(true)
        {
            rc=WaitForSingleObject(eProcessed,INFINITE);
            if (rc== WAIT_OBJECT_0)
            {   
                do
                {
                    if(k->bPrsd)
                    {
                        continue;
                    }
                    else
                    {   
                        if(!k)
                        {break;}
                        k->bPrsd = TRUE;
    #ifdef DEBUG_NET
                        SendStruct(...);
    #endif
                    }
                    if(k->next == NULL || k->next->bPrsd ==TRUE || !(k->next->bFull))
                    {
                        ResetEvent(eProcessed);
                        break;
                    }
                } while (k = k->next); // next element after each loop
            }
        }
        return 1;
    }

详：

现在有些事情让我相信错误不在那里，因为子字符串错误非常罕见。我只能在按 Mouse_Down+Wnd+Tab 滚动窗口并保持一段时间时以 100% 的机会重现它（当然在其他情况下也发生了）。我避免发布整个代码，因为它有点大，混乱是不可避免的。如果错误不在这里，我将编辑帖子并添加更多代码。

提前致谢