PVS-Studio warning V547 for IPP Samples

typedef unsigned int    Ipp32u;

UMC::Status Init(..., Ipp32u memSize, ...)
{
  ...
  memSize -= UMC::align_value<Ipp32u>(m_nFrames*sizeof(Frame));
  if(memSize < 0)
      return UMC::UMC_ERR_NOT_ENOUGH_BUFFER;
  ...
}

This suspicious code was found in IPP Samples project by PVS-Studio static code analyzer.
Warning message is:
V547 Expression 'memSize < 0' is always false. Unsigned type value is never < 0. vc1_enc umc_vc1_enc_planes.h 200

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