VC++ Access violation reading from private member value types (bool)

Question

I am getting this weird error where I get an access violation from reading private class-level values (no pointers).

HRESULT WindowedSinkRenderer::Initialize(IMLTeeSink3 *sink)
{
    std::cout << "Test\n";

    // exception throw here
    std::cout << "Test" << _isInitialized << "\n";

    std::cout << "Test\n";

    return S_OK;
}

Here is my header

class WindowedSinkRenderer
{
public:
    WindowedSinkRenderer();
    ~WindowedSinkRenderer();

    HRESULT Initialize(IMLTeeSink3 *sink);
    HRESULT Deinitialize();
    HRESULT SetRenderOwner(HWND handle);
    HRESULT SetRenderDimensions(int width, int height, bool fillVideo);
    HRESULT GetCurrentImage(BITMAPINFOHEADER* bitmapHeader, BYTE** data, DWORD* size, bool* bufferHasInfoHeader);

private:

    DWORD _remoteGraphRegister;
    SmartPtr<IGraphBuilder> _graphBuilder;
    SmartPtr<IFilterGraph2> _filterGraph;
    SmartPtr<IMediaControl> _mediaControl;
    WindowedVideoRenderer* _videoRenderer;

    bool _isInitialized;

};

And here is my constructor where it event initializes the bool to false.

WindowedSinkRenderer::WindowedSinkRenderer() : _isInitialized(false)
{

}

What gives? Why the error?

0xC0000005: Access violation reading location 0xCDCDCDE1.

Please show code where you call WindowedSinkRenderer::Initialize() — Tony J
The pattern 0xcdcdcdcd is the typical pattern of uninitialized memory (see e.g. this page for a reference). 0xCDCDCDE1 seems like an offset from an uninitialized pointer. — Some programmer dude
@JoachimPileborg It was an invalid pointer to a WindowedSinkRenderer. It threw me off because I could still execute code in the method, provided that I treat the method as a static method (not accessing instance members). — Paul Knopf

ScottMcP-MVP ScottMcP-MVP · Accepted Answer · 2015-06-18T18:28:42

It looks like you are calling Initialize with an invalid pointer to a WindowedSinkRenderer object.

VC++ Access violation reading from private member value types (bool)

1 Answers