PVS-Studio warning V547 for Shareaza

inline void CXmlReader::CXmlInputStream::UnsafePutCharsBack(
  const TCHAR* pChars, size_t nNumChars)
{
  if (nNumChars > 0)
  {
    for (size_t nCharPos = nNumChars - 1;
         nCharPos >= 0;
         --nCharPos)
      UnsafePutCharBack(pChars[nCharPos]);
  }
}

Infinite loop.

This suspicious code was found in Shareaza project by PVS-Studio static code analyzer.
Warning message is:
V547 Expression 'nCharPos >= 0' is always true. Unsigned type value is always >= 0. BugTrap xmlreader.h 946

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