Examples of errors detected by the V658 diagnostic

V658. Value is subtracted from unsigned variable. It can result in an overflow. In such a case, the comparison operation may behave unexpectedly.

VCMI

V658 A value is being subtracted from the unsigned variable. This can result in an overflow. In such a case, the '<' comparison operation can potentially behave unexpectedly. Consider inspecting the 'i < cs.spells.size() - 2' expression. CGameHandler.cpp 760

void CGameHandler::endBattleConfirm(....)
{
  ....
  for (int i = 0; i < cs.spells.size(); i++)
  {
    names << "%s";
    if (i < cs.spells.size() - 2)
      names << ", ";
    else if (i < cs.spells.size() - 1)
      names << "%s";
  }
  ....
}