From b6ac0cd90ac3bdd1c464dc3a1d304772769bb75b Mon Sep 17 00:00:00 2001
From: Hallvard Furuseth <hallvard@openldap.org>
Date: Sat, 4 Jul 2015 13:48:02 +0200
Subject: [PATCH] mdb_drop0(): Omit scanning DUPSORT sub-DB leaves

---
 libraries/liblmdb/mdb.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/libraries/liblmdb/mdb.c b/libraries/liblmdb/mdb.c
index 7cf5294..1de63e2 100644
--- a/libraries/liblmdb/mdb.c
+++ b/libraries/liblmdb/mdb.c
@@ -9470,8 +9470,10 @@ mdb_drop0(MDB_cursor *mc, int subs)
 		MDB_cursor mx;
 		unsigned int i;
 
-		/* LEAF2 pages have no nodes, cannot have sub-DBs */
-		if (IS_LEAF2(mc->mc_pg[mc->mc_top]))
+		/* DUPSORT sub-DBs have no ovpages/DBs. Omit scanning leaves.
+		 * This also avoids any P_LEAF2 pages, which have no nodes.
+		 */
+		if (mc->mc_flags & C_SUB)
 			mdb_cursor_pop(mc);
 
 		mdb_cursor_copy(mc, &mx);