Subject: Re: pgsql: Add deduplication to nbtree.
To: Peter Geoghegan <pg@bowt.ie>, pgsql-committers@lists.postgresql.org
References: <E1j73sn-0003FQ-KO@gemulon.postgresql.org>
From: Peter Eisentraut <peter.eisentraut@2ndquadrant.com>
Organization: 2ndQuadrant
Message-ID: <21800dbe-a13e-22f7-d423-b81db9d249f5@2ndquadrant.com>
Date: Thu, 30 Apr 2020 20:33:19 +0200
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On 2020-02-26 22:06, Peter Geoghegan wrote:
> Add deduplication to nbtree.

AddressSanitizer has a use-after-scope complaint related to this patch.

The following change fixes it:

diff --git a/src/backend/access/nbtree/nbtinsert.c b/src/backend/access/nbtree/nbtinsert.c
index a70b64d964..8246ab4f18 100644
--- a/src/backend/access/nbtree/nbtinsert.c
+++ b/src/backend/access/nbtree/nbtinsert.c
@@ -1289,6 +1289,7 @@ _bt_insertonpg(Relation rel,
 			xl_btree_metadata xlmeta;
 			uint8		xlinfo;
 			XLogRecPtr	recptr;
+			uint16		upostingoff;
 
 			xlrec.offnum = newitemoff;
 
@@ -1354,7 +1355,7 @@ _bt_insertonpg(Relation rel,
 				 * must reconstruct final itup (as well as nposting) using
 				 * _bt_swap_posting().
 				 */
-				uint16		upostingoff = postingoff;
+				upostingoff = postingoff;
 
 				XLogRegisterBufData(0, (char *) &upostingoff, sizeof(uint16));
 				XLogRegisterBufData(0, (char *) origitup,

Please check.

-- 
Peter Eisentraut              http://www.2ndQuadrant.com/
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