PVS-Studio warning V507 for Source SDK

static Activity DetermineExpressionMoveActivity(
  CChoreoEvent *event, CAI_BaseNPC *pNPC )
{
  ....
  const char *pszAct = Q_strstr( sParam2, " " );
  if ( pszAct )
  {
    char szActName[256];
    Q_strncpy( szActName, sParam2, sizeof(szActName) );
    szActName[ (pszAct-sParam2) ] = '\0';
    pszAct = szActName;
  }
  ....
}

This suspicious code was found in Source SDK project by PVS-Studio static code analyzer.
Warning message is:
V507 Pointer to local array 'szActName' is stored outside the scope of this array. Such a pointer will become invalid. Server (HL2) baseflex.cpp 1326

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