I am writing a wrapper class to call _CrtDumpMemoryLeaks() in WPF application. I am

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Asked: May 22, 20262026-05-22T23:06:49+00:00 2026-05-22T23:06:49+00:00

I am writing a wrapper class to call _CrtDumpMemoryLeaks() in WPF application. I am

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I am writing a wrapper class to call _CrtDumpMemoryLeaks() in WPF application. I am loading a C language DLL in the WPF application and would like to see if the there are any memory leaks in the DLL as WPF is acting as a test app for DLL also.

class MemLeak
{
    static int _CRTDBG_ALLOC_MEM_DF   =  0x01;
    static int _CRTDBG_LEAK_CHECK_DF  =  0x20;        
    static int _CRTDBG_MODE_DEBUG     =  0x2;
    static int _CRTDBG_MODE_WNDW      =  0x4;
    static int _CRT_WARN              =  0;
    static int _CRT_ERROR             =  1;
    static int _CRT_ASSERT            =  2;

    [DllImportAttribute("msvcrtd.dll", EntryPoint = "_CrtDumpMemoryLeaks", SetLastError = true)]
    static extern int _CrtDumpMemoryLeaks();

    [DllImportAttribute("msvcrtd.DLL", EntryPoint = "_CrtSetDbgFlag")]
    static extern int _CrtSetDbgFlag(int newFlag);

    [DllImportAttribute("msvcrtd.DLL", EntryPoint = "_CrtSetReportMode")]
    static extern int _CrtSetReportMode(int reportType, int reportMode);

    public static void StartMemLeakLogging()
    {
        _CrtSetDbgFlag(_CRTDBG_ALLOC_MEM_DF | _CRTDBG_LEAK_CHECK_DF);
        _CrtSetReportMode(_CRT_ERROR | _CRT_WARN | _CRT_ASSERT, _CRTDBG_MODE_DEBUG);
    }

    public static void StopMemLeakLogging()
    {
        _CrtSetReportMode(_CRT_ERROR | _CRT_WARN | _CRT_ASSERT, _CRTDBG_MODE_DEBUG | _CRTDBG_MODE_WNDW);
        int i = _CrtDumpMemoryLeaks();
    }
}

I am using Visual Studio 2008 SP1 on Windows XP Professional SP3. Strangely I had to download the msvcrtd.dll file because the system could not find it. After that, just copied it to the debug folder and the application started working. However, I don’t see the memory leak information in the output window during the debugging even if I intentionally allocated memory and not free in the DLL code.

Also, I cannot change the source code of the DLL else would have tried putting these functions in the DLL source code. I tried creating a MFC application and calling DLL functions, the MFC application detects the memory leaks and displays in the output window even if I dont call the _CrtDumpMemoryLeaks() because I think MFC in debug might internally be calling this function but it doesnt work with WPF test app.