PVS-Studio warning V547 for TortoiseSVN

typedef index_t revision_t;
...
void CCacheLogQuery::InternalLog (
   revision_t startRevision
 , revision_t endRevision
 , const CDictionaryBasedTempPath& startPath
 , int limit
 , const CLogOptions& options)
{
  ...
  // we cannot receive logs for rev < 0
  if (endRevision < 0)
    endRevision = 0;

  ...
}

Negative values simply cannot appear here. The endRevision variable has the unsigned type and, therefore, endRevision is always >=0. The potential danger is this: if a negative value was cast to the unsigned type somewhere before, we will be handling a very big number. And there's no check for that.

This suspicious code was found in TortoiseSVN project by PVS-Studio static code analyzer.
Warning message is:
V547 Expression 'endRevision < 0' is always false. Unsigned type value is never < 0. cachelogquery.cpp 999

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