Remove overzealous _bt_split() assertions.

petergeoghegan · petergeoghegan · commit 1e07f5e0a1cf · 2020-03-02T21:40:11.000-08:00
_bt_split() is passed NULL as its insertion scankey for internal page splits. Two recently added Assert() statements failed to consider this, leading to a crash with pg_upgrade'd BREE_VERSION < 4 indexes. Remove the assertions. The assertions in question were added by commit 0d861bb, which added nbtree deduplication. It would be possible to fix the assertions directly instead, but they weren't adding much anyway.
diff --git a/src/backend/access/nbtree/nbtinsert.c b/src/backend/access/nbtree/nbtinsert.c
@@ -1632,7 +1632,6 @@ _bt_split(Relation rel, BTScanInsert itup_key, Buffer buf, Buffer cbuf,
 	 */
 	leftoff = P_HIKEY;
 
-	Assert(BTreeTupleIsPivot(lefthikey) || !itup_key->heapkeyspace);
 	Assert(BTreeTupleGetNAtts(lefthikey, rel) > 0);
 	Assert(BTreeTupleGetNAtts(lefthikey, rel) <= indnkeyatts);
 	if (PageAddItem(leftpage, (Item) lefthikey, itemsz, leftoff,
@@ -1697,7 +1696,6 @@ _bt_split(Relation rel, BTScanInsert itup_key, Buffer buf, Buffer cbuf,
 		itemid = PageGetItemId(origpage, P_HIKEY);
 		itemsz = ItemIdGetLength(itemid);
 		item = (IndexTuple) PageGetItem(origpage, itemid);
-		Assert(BTreeTupleIsPivot(item) || !itup_key->heapkeyspace);
 		Assert(BTreeTupleGetNAtts(item, rel) > 0);
 		Assert(BTreeTupleGetNAtts(item, rel) <= indnkeyatts);
 		if (PageAddItem(rightpage, (Item) item, itemsz, rightoff,
