From 7083e58e2e8c76e54f48591e545eb1ae7051fb33 Mon Sep 17 00:00:00 2001
From: Sergei Petrunia <sergey@mariadb.com>
Date: Tue, 16 May 2023 11:04:48 +0300
Subject: [PATCH] Fix UBSAN failure: sql_select.h:982:7: load of value ... not
 valid for type bool

This is 11.0 part of the fix: in 11.0, get_costs_for_tables() calls
best_access_path() for all possible tables, for each call it saves
a POSITION object with the access method and "loose_scan_pos"
POSITION object.
The latter is saved even if there is no possible LooseScan plan. Saving
is done by copying POSITION objects which may generate a spurious
UBSan error.
---
 sql/sql_select.cc | 1 +
 1 file changed, 1 insertion(+)

diff --git a/sql/sql_select.cc b/sql/sql_select.cc
index cec3aa1f91f..9d1987a6369 100644
--- a/sql/sql_select.cc
+++ b/sql/sql_select.cc
@@ -449,6 +449,7 @@ POSITION::POSITION()
   key= 0;
   forced_index= 0;
   use_join_buffer= 0;
+  firstmatch_with_join_buf= false;
   sj_strategy= SJ_OPT_NONE;
   n_sj_tables= 0;
   spl_plan= 0;