From: Alexander Korotkov <akorotkov@postgresql.org>
Date: Tue, 24 Sep 2019 22:47:36 +0000 (+0300)
Subject: Fix bug in pairingheap_SpGistSearchItem_cmp()
X-Git-Tag: REL_13_BETA1~1440
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=90c0987258264de07780f0329db2fce83098fba8;p=thirdparty%2Fpostgresql.git

Fix bug in pairingheap_SpGistSearchItem_cmp()

Our item contains only so->numberOfNonNullOrderBys of distances.  Reflect that
in the loop upper bound.

Discussion: https://postgr.es/m/53536807-784c-e029-6e92-6da802ab8d60%40postgrespro.ru
Author: Nikita Glukhov
Backpatch-through: 12
---

diff --git a/src/backend/access/spgist/spgscan.c b/src/backend/access/spgist/spgscan.c
index cfba47067cc..6e940fd3def 100644
--- a/src/backend/access/spgist/spgscan.c
+++ b/src/backend/access/spgist/spgscan.c
@@ -56,7 +56,7 @@ pairingheap_SpGistSearchItem_cmp(const pairingheap_node *a,
 	else
 	{
 		/* Order according to distance comparison */
-		for (i = 0; i < so->numberOfOrderBys; i++)
+		for (i = 0; i < so->numberOfNonNullOrderBys; i++)
 		{
 			if (isnan(sa->distances[i]) && isnan(sb->distances[i]))
 				continue;		/* NaN == NaN */