PVS-Studio warning V598 for IPP Samples

class _MediaDataEx {
  ...
  virtual bool TryStrongCasting(
    pDynamicCastFunction pCandidateFunction) const;
  virtual bool TryWeakCasting(
    pDynamicCastFunction pCandidateFunction) const;
};

Status VC1Splitter::Init(SplitterParams& rInit)
{
  MediaDataEx::_MediaDataEx *m_stCodes;
  ...
  m_stCodes = (MediaDataEx::_MediaDataEx *)
    ippsMalloc_8u(START_CODE_NUMBER*2*sizeof(Ipp32s)+
                  sizeof(MediaDataEx::_MediaDataEx));
  ...
  memset(m_stCodes, 0,
    (START_CODE_NUMBER*2*sizeof(Ipp32s)+
    sizeof(MediaDataEx::_MediaDataEx)));
  ...
}

This suspicious code was found in IPP Samples project by PVS-Studio static code analyzer.
Warning message is:
V598 The 'memset' function is used to nullify the fields of '_MediaDataEx' class. Virtual method table will be damaged by this. vc1_spl umc_vc1_spl.cpp 131

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