static void sqlite3SelectExpand(Parse *pParse, Select *pSelect){
  Walker w;
  w.xExprCallback = sqlite3ExprWalkNoop;
  w.pParse = pParse;
  if( OK_IF_ALWAYS_TRUE(pParse->hasCompound) ){
    w.xSelectCallback = convertCompoundSelectToSubquery;
    w.xSelectCallback2 = 0;
    sqlite3WalkSelect(&w, pSelect);
  }
  w.xSelectCallback = selectExpander;
  w.xSelectCallback2 = selectPopWith;
  sqlite3WalkSelect(&w, pSelect);
}
Unknown