Fix another place broken by new List implementation :-(. Per example

from goranpop@nspoint.net.  I think this escaped notice because in
simple cases the list is NIL on entry.
This commit is contained in:
Tom Lane 2004-12-15 21:13:34 +00:00
parent 84dbd5a8f6
commit dd29fc2f61
1 changed files with 9 additions and 4 deletions

View File

@ -6,7 +6,7 @@
* Portions Copyright (c) 1996-2004, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/backend/optimizer/geqo/geqo_eval.c,v 1.71 2004/08/29 05:06:43 momjian Exp $
* $PostgreSQL: pgsql/src/backend/optimizer/geqo/geqo_eval.c,v 1.72 2004/12/15 21:13:34 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -80,12 +80,17 @@ geqo_eval(Gene *tour, int num_gene, GeqoEvalData *evaldata)
oldcxt = MemoryContextSwitchTo(mycontext);
/*
* preserve root->join_rel_list, which gimme_tree changes; without
* this, it'll be pointing at recycled storage after the
* MemoryContextDelete below.
* gimme_tree will add entries to root->join_rel_list, which may or may
* not already contain some entries. The newly added entries will be
* recycled by the MemoryContextDelete below, so we must ensure that
* the list is restored to its former state before exiting. With the
* new List implementation, the easiest way is to make a duplicate list
* that gimme_tree can modify.
*/
savelist = evaldata->root->join_rel_list;
evaldata->root->join_rel_list = list_copy(savelist);
/* construct the best path for the given combination of relations */
joinrel = gimme_tree(tour, num_gene, evaldata);