PVS-Studio warning V519 for QT

void HtmlGenerator::generateHeader(....)
{
  ...
  QString shortVersion;
  shortVersion = project + " " + shortVersion + ": ";
  if (node && !node->doc().location().isEmpty())
      out() << "<!-- " << node->doc().location().fileName() <<
      " -->\n";

  shortVersion = myTree->version();
  ...
}

Most likely this is what should be written here: shortVersion += myTree->version();

This suspicious code was found in QT project by PVS-Studio static code analyzer.
Warning message is:
V519 The 'shortVersion' variable is assigned values twice successively. Perhaps this is a mistake. Check lines: 1791, 1795. qdoc3 htmlgenerator.cpp 1795

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