diff --git a/lmdb.h b/lmdb.h
index a933f817..af495876 100644
--- a/lmdb.h
+++ b/lmdb.h
@@ -341,7 +341,8 @@ typedef void (MDB_rel_func)(MDB_val *item, void *oldptr, void *newptr, void *rel
 #define MDB_REVERSEKEY	0x02
 	/** use sorted duplicates */
 #define MDB_DUPSORT		0x04
-	/** numeric keys in native byte order: either unsigned int or size_t.
+	/** numeric keys in native byte order, either unsigned int or #mdb_size_t.
+	 *	(lmdb expects 32-bit int <= size_t <= 32/64-bit mdb_size_t.)
 	 *  The keys must all be of the same size. */
 #define MDB_INTEGERKEY	0x08
 	/** with #MDB_DUPSORT, sorted dup items have fixed size */
@@ -1181,7 +1182,8 @@ int  mdb_txn_renew(MDB_txn *txn);
 	 *		keys must be unique and may have only a single data item.
 	 *	<li>#MDB_INTEGERKEY
 	 *		Keys are binary integers in native byte order, either unsigned int
-	 *		or size_t, and will be sorted as such.
+	 *		or #mdb_size_t, and will be sorted as such.
+	 *		(lmdb expects 32-bit int <= size_t <= 32/64-bit mdb_size_t.)
 	 *		The keys must all be of the same size.
 	 *	<li>#MDB_DUPFIXED
 	 *		This flag may only be used in combination with #MDB_DUPSORT. This option
diff --git a/mdb.c b/mdb.c
index 590947ed..1cb996e0 100644
--- a/mdb.c
+++ b/mdb.c
@@ -5399,10 +5399,8 @@ mdb_page_get(MDB_txn *txn, pgno_t pgno, MDB_page **ret, int *lvl)
 			if (tx2->mt_spill_pgs) {
 				MDB_ID pn = pgno << 1;
 				x = mdb_midl_search(tx2->mt_spill_pgs, pn);
-				if (x <= tx2->mt_spill_pgs[0] && tx2->mt_spill_pgs[x] == pn) {
-					p = (MDB_page *)(env->me_map + env->me_psize * pgno);
-					goto done;
-				}
+				if (x <= tx2->mt_spill_pgs[0] && tx2->mt_spill_pgs[x] == pn)
+					goto mapped;
 			}
 			if (dl[0].mid) {
 				unsigned x = mdb_mid2l_search(dl, pgno);
@@ -5415,14 +5413,15 @@ mdb_page_get(MDB_txn *txn, pgno_t pgno, MDB_page **ret, int *lvl)
 		} while ((tx2 = tx2->mt_parent) != NULL);
 	}
 
-	if (likely(pgno < txn->mt_next_pgno)) {
-		level = 0;
-		p = (MDB_page *)(env->me_map + env->me_psize * pgno);
-	} else {
+	if (unlikely(pgno >= txn->mt_next_pgno)) {
 		mdb_debug("page %zu not found", pgno);
 		txn->mt_flags |= MDB_TXN_ERROR;
 		return MDB_PAGE_NOTFOUND;
 	}
+	level = 0;
+
+mapped:
+	p = (MDB_page *)(env->me_map + env->me_psize * pgno);
 
 done:
 	*ret = p;