static void rtreeFreeCallback(void *p){
  RtreeGeomCallback *pInfo = (RtreeGeomCallback*)p;
  if( pInfo->xDestructor ) pInfo->xDestructor(pInfo->pContext);
  sqlite3_free(p);
}
static void rtreeFreeCallback(void *p){
  RtreeGeomCallback *pInfo = (RtreeGeomCallback*)p;
  if( pInfo->xDestructor ) pInfo->xDestructor(pInfo->pContext);
  sqlite3_free(p);
}