WinCE下GetDC内存泄露的bug

今天偶然发现微软wince系统下mfc的一个bug，微软的网站上也有记录，如下：

    BUG: Memory leaks when you use the CWnd class versions of the GetDC method and the ReleaseDC method

    When you run code that calls the CWnd::GetDC function followed by the CWnd::ReleaseDC function, a memory leak of 4 bytes occurs. The cause of this bug is currently unknown. To avoid this problem, do not use the CWnd class versions of the GetDC method and the ReleaseDC method. Use the GetDC function and the ReleaseDC function. Microsoft has confirmed that this is a bug in the Microsoft products that are listed at the beginning of this article.

    Steps to Reproduce the Behavior

In a method that is a part of a class that is derived from CWnd, insert the following code in your application:

    CDC *pDC;

    RECT rect; 

    GetClientRect (&rect);

 

    for (int i = 0; i < 1000; i++)

    {

        pDC = GetDC ();

        ReleaseDC (pDC);

}

 If you run this code and then check the system memory before and after you run the code, you notice that the system memory leaks four bytes per iteration. If you change the code to the following code, the memory leak does not occur:
     HDC hDC;
    RECT rect;

    ::GetClientRect (m_hWnd, &rect);

 

    for (int i = 0; i < 1000; i++)

    {

        hDC = ::GetDC (m_hWnd);

        ::DrawText (hDC, L"Testing...", 10, &rect, DT_CENTER);

        ::ReleaseDC (m_hWnd, hDC);

    }