**   (1) The data to be sorted has already been packed into a Record
  **       by a prior OP_MakeRecord.  In this case nData==1 and regData
  **       will be completely unrelated to regOrigData.
  **   (2) All output columns are included in the sort record.  In that
  **       case regData==regOrigData.
  **   (3) Some output columns are omitted from the sort record due to
  **       the SQLITE_ENABLE_SORTER_REFERENCE optimization, or due to the
  **       SQLITE_ECEL_OMITREF optimization.  In that case, regOrigData==0

  **       to prevent this routine from trying to copy values that might
  **       not exist.

  */
  assert( nData==1 || regData==regOrigData || regOrigData==0 );

  if( nPrefixReg ){
    assert( nPrefixReg==nExpr+bSeq );
    regBase = regData - nPrefixReg;
  }else{
................................................................................
    if( p->iLimit
     && (ecelFlags & SQLITE_ECEL_OMITREF)!=0 
     && nPrefixReg>0
    ){
      assert( pSort!=0 );
      assert( hasDistinct==0 );
      pSort->pDeferredRowLoad = &sRowLoadInfo;

    }else{
      innerLoopLoadRow(pParse, p, &sRowLoadInfo);
    }
  }

  /* If the DISTINCT keyword was present on the SELECT statement
  ** and this row has been seen before, then do not make this row

  **   (1) The data to be sorted has already been packed into a Record
  **       by a prior OP_MakeRecord.  In this case nData==1 and regData
  **       will be completely unrelated to regOrigData.
  **   (2) All output columns are included in the sort record.  In that
  **       case regData==regOrigData.
  **   (3) Some output columns are omitted from the sort record due to
  **       the SQLITE_ENABLE_SORTER_REFERENCE optimization, or due to the
  **       SQLITE_ECEL_OMITREF optimization, or due to the 
  **       SortCtx.pDeferredRowLoad optimiation.  In any of these cases
  **       regOrigData is 0 to prevent this routine from trying to copy

  **       values that might not yet exist.
  */
  assert( nData==1 || regData==regOrigData || regOrigData==0 );

  if( nPrefixReg ){
    assert( nPrefixReg==nExpr+bSeq );
    regBase = regData - nPrefixReg;
  }else{
................................................................................
    if( p->iLimit
     && (ecelFlags & SQLITE_ECEL_OMITREF)!=0 
     && nPrefixReg>0
    ){
      assert( pSort!=0 );
      assert( hasDistinct==0 );
      pSort->pDeferredRowLoad = &sRowLoadInfo;
      regOrig = 0;
    }else{
      innerLoopLoadRow(pParse, p, &sRowLoadInfo);
    }
  }

  /* If the DISTINCT keyword was present on the SELECT statement
  ** and this row has been seen before, then do not make this row

  CREATE TABLE t1(x INTEGER PRIMARY KEY);
  INSERT INTO t1 VALUES(1),(2);
  DROP TABLE IF EXISTS t2;
  CREATE TABLE t2(y);
  INSERT INTO t2 VALUES(9),(8),(3),(4);
  SELECT (SELECT x||y FROM t2, t1 ORDER BY x, y);
} {13}












finish_test

  CREATE TABLE t1(x INTEGER PRIMARY KEY);
  INSERT INTO t1 VALUES(1),(2);
  DROP TABLE IF EXISTS t2;
  CREATE TABLE t2(y);
  INSERT INTO t2 VALUES(9),(8),(3),(4);
  SELECT (SELECT x||y FROM t2, t1 ORDER BY x, y);
} {13}

# Problem found by OSSFuzz on 2018-05-05.  This was caused by a new
# optimization that had not been previously released.
#
do_execsql_test 10.0 {
  CREATE TABLE t10(a,b);
  INSERT INTO t10 VALUES(1,2),(8,9),(3,4),(5,4),(0,7);
  CREATE INDEX t10b ON t10(b);
  SELECT b, rowid, '^' FROM t10 ORDER BY b, a LIMIT 4;
} {2 1 ^ 4 3 ^ 4 4 ^ 7 5 ^}


finish_test