PVS-Studio warning V595 for Firefox

nsresult
ShortcutResolver::Init()
{
    CoInitialize(NULL);  // FIX: we should probably move
                         // somewhere higher up during startup

    HRESULT hres;
    hres = CoCreateInstance(CLSID_ShellLink,
                            NULL,
                            CLSCTX_INPROC_SERVER,
                            IID_IShellLinkW,
                            (void**)&(mShellLink));
    if (SUCCEEDED(hres))
    {
        // Get a pointer to the IPersistFile interface.
        hres = mShellLink->QueryInterface(
          IID_IPersistFile, (void**)&mPersistFile);
    }

    if (mPersistFile == nsnull || mShellLink == nsnull)
        return NS_ERROR_FAILURE;

    return NS_OK;
}

This suspicious code was found in Firefox project by PVS-Studio static code analyzer.
Warning message is:
V595 The 'mShellLink' pointer was utilized before it was verified against nullptr. Check lines: 183, 187. nslocalfilewin.cpp 183

PVS-Studio is a static analyzer for detecting bugs in the source code of applications written in C, C++, C++11, C++/CX. Site: http://www.viva64.com/en/pvs-studio/