Strange "Memory Leak Detection" error C++

Question

I have a very strange problem with memory leaks. I use _CrtDumpMemoryLeaks for checking leaks. Here is my WinMain function:

int APIENTRY _tWinMain(_In_ HINSTANCE hInstance,
                     _In_opt_ HINSTANCE hPrevInstance,
                     _In_ LPTSTR    lpCmdLine,
                     _In_ int       nCmdShow)
{
    UNREFERENCED_PARAMETER(hPrevInstance);
    UNREFERENCED_PARAMETER(lpCmdLine);

    ////////////////// SET UP CHECKS FOR MEMORY LEAKS ////////////////////
    _CrtSetDbgFlag( _CRTDBG_ALLOC_MEM_DF | _CRTDBG_LEAK_CHECK_DF );
    //////////////////////////////////////////////////////////////////////


    _CrtDumpMemoryLeaks(); // Reports leaks to stderr

    return 0;
}

As you can see, I have removed completely everything from it just to check if maybe I get some kind of false alarms.

After I close an application, I get this bunch of memory leaks in the output:

Detected memory leaks!
Dumping objects ->
{1343} normal block at 0x06076780, 8 bytes long.
 Data: < g      > 20 67 07 06 00 00 00 00 
{1342} normal block at 0x06076710, 52 bytes long.
 Data: <@   @   @       > 40 16 07 06 40 16 07 06 40 16 07 06 01 00 CD CD 
{1341} normal block at 0x060766B0, 32 bytes long.
 Data: <C:/Windows/Fonts> 43 3A 2F 57 69 6E 64 6F 77 73 2F 46 6F 6E 74 73 
{1339} normal block at 0x0607F438, 16 bytes long.
 Data: <              P > C0 17 0B 01 01 00 00 00 01 00 00 00 80 13 50 04 
{1338} normal block at 0x04501380, 8 bytes long.
 Data: <    H   > BC 0D 0B 01 48 18 07 06 
{1295} normal block at 0x060716B0, 8 bytes long.
 Data: <        > B4 B3 0B 01 00 00 00 00 
{1294} normal block at 0x06071640, 52 bytes long.
 Data: < g   g   g      > 10 67 07 06 10 67 07 06 10 67 07 06 01 01 CD CD 
{1293} normal block at 0x0450DFB8, 8 bytes long.
 Data: < !    P > E0 21 0B 01 98 05 50 04 
{1292} normal block at 0x0450E110, 8 bytes long.
 Data: <  P     > E8 05 50 04 00 00 00 00 
// (There's like thousand more of those...)
Object dump complete.

I have completely no idea where do them come from.

Thanks in advance for any answer.

Answer 1

Check the Output window. Do you see a bunch of DLLs being loaded? Any of them may be statically initializing data structures that are not freed before you call the leak output. Try the tip here to exclude some of that noise, by bracketing your leak check to a certain range of execution time.

Since the statically initialized Google Test singleton requires allocations on the heap, the Visual C++ memory leak detector will report memory leaks at the end of the program run. The easiest way to avoid this is to use the _CrtMemCheckpoint and _CrtMemDumpAllObjectsSince calls to not report any statically initialized heap objects. See MSDN for more details and additional heap check/debug routines.