Merge branch '10.2' into 10.3

# Conflicts: # mysql-test/suite/galera/r/MW-388.result # mysql-test/suite/galera/t/MW-388.test # mysql-test/suite/innodb/r/truncate_inject.result # mysql-test/suite/innodb/t/truncate_inject.test # mysql-test/suite/rpl/r/rpl_stop_slave.result # mysql-test/suite/rpl/t/rpl_stop_slave.test # sql/sp_head.cc # sql/sp_head.h # sql/sql_lex.cc # sql/sql_yacc.yy # storage/xtradb/buf/buf0dblwr.cc
author: Sergei Petrunia <psergey@askmonty.org> 2020-01-17 00:46:40 +0300
committer: Sergei Petrunia <psergey@askmonty.org> 2020-01-17 00:46:40 +0300
commit: e709eb9bf712006d070767629518f827cd2f6bed (patch)
tree: 103290899cbe2a67f78277e0e33486e51ef01717
parent: d531b4ee3a9bcd89a2fa6b49a2207eaf966f53e3 (diff)
parent: b04429434ad1ee7f49d263762a560f4ff31dd111 (diff)
download: mariadb-git-e709eb9bf712006d070767629518f827cd2f6bed.tar.gz
219 files changed, 841 insertions, 524 deletions
diff --git a/mysql-test/include/binlog_inject_error.inc b/mysql-test/include/binlog_inject_error.inc
index 383f66ba843..ce940352723 100644
--- a/mysql-test/include/binlog_inject_error.inc
+++ b/mysql-test/include/binlog_inject_error.inc
@@ -13,10 +13,10 @@
 # let query= 'CREATE TABLE t1 (a INT)';
 # source include/binlog_inject_error.inc;
 #
-
+set @saved_dbug = @@global.debug_dbug;
 SET GLOBAL debug_dbug='d,injecting_fault_writing';
 --echo $query;
 --replace_regex /(errno: .*)/(errno: #)/
 --error ER_ERROR_ON_WRITE
 --eval $query
-SET GLOBAL debug_dbug='';
+set @@global.debug_dbug = @saved_dbug;
diff --git a/mysql-test/main/cache_temporal_4265.result b/mysql-test/main/cache_temporal_4265.result
index 7f215de43fb..1cda7004a6f 100644
--- a/mysql-test/main/cache_temporal_4265.result
+++ b/mysql-test/main/cache_temporal_4265.result
@@ -1,13 +1,12 @@
 create table t1 (a date);
 insert t1 values ('2000-01-02'), ('2001-02-03'), ('2002-03-04');
-set debug_dbug='d,str_to_datetime_warn';
+SET STATEMENT debug_dbug='d,str_to_datetime_warn' for
 select * from t1 where a > date_add('2000-01-01', interval 5 day);
 a
 2001-02-03
 2002-03-04
 Warnings:
 Note	1003	2000-01-01
-set debug_dbug='';
 drop table t1;
 create table t1 (id int not null, ut timestamp(6) not null);
 insert into t1 values(1, '2001-01-01 00:00:00.2');
diff --git a/mysql-test/main/cache_temporal_4265.test b/mysql-test/main/cache_temporal_4265.test
index c62f3c3c506..1af683c617b 100644
--- a/mysql-test/main/cache_temporal_4265.test
+++ b/mysql-test/main/cache_temporal_4265.test
@@ -5,9 +5,9 @@
 
 create table t1 (a date);
 insert t1 values ('2000-01-02'), ('2001-02-03'), ('2002-03-04');
-set debug_dbug='d,str_to_datetime_warn';
-select * from t1 where a > date_add('2000-01-01', interval 5 day);
-set debug_dbug='';
+
+SET STATEMENT debug_dbug='d,str_to_datetime_warn' for
+	select * from t1 where a > date_add('2000-01-01', interval 5 day);
 drop table t1;
 
 #
diff --git a/mysql-test/main/create_or_replace2.result b/mysql-test/main/create_or_replace2.result
index 47431212492..6be0d46bdc1 100644
--- a/mysql-test/main/create_or_replace2.result
+++ b/mysql-test/main/create_or_replace2.result
@@ -4,9 +4,9 @@ drop table if exists t1;
 SET @old_debug= @@session.debug;
 CREATE TABLE t1 (i INT, KEY(i)) ENGINE=InnoDB;
 CREATE OR REPLACE TEMPORARY TABLE tmp (a int, b int, key(a)) engine=myisam;
-set debug_dbug='+d,send_kill_after_delete';
+SET debug_dbug='+d,send_kill_after_delete';
 CREATE OR REPLACE TABLE t1 LIKE tmp;
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 SHOW TABLES;
 Tables_in_test
 t1
diff --git a/mysql-test/main/create_or_replace2.test b/mysql-test/main/create_or_replace2.test
index 199e5523811..80c8b635d8d 100644
--- a/mysql-test/main/create_or_replace2.test
+++ b/mysql-test/main/create_or_replace2.test
@@ -19,9 +19,9 @@ SET @old_debug= @@session.debug;
 
 CREATE TABLE t1 (i INT, KEY(i)) ENGINE=InnoDB;
 CREATE OR REPLACE TEMPORARY TABLE tmp (a int, b int, key(a)) engine=myisam;
-set debug_dbug='+d,send_kill_after_delete';
+SET debug_dbug='+d,send_kill_after_delete';
 CREATE OR REPLACE TABLE t1 LIKE tmp;
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 SHOW TABLES;
 show create table t1;
 --sync_slave_with_master
diff --git a/mysql-test/main/drop_bad_db_type.result b/mysql-test/main/drop_bad_db_type.result
index 1b691957877..ae6fe708e60 100644
--- a/mysql-test/main/drop_bad_db_type.result
+++ b/mysql-test/main/drop_bad_db_type.result
@@ -1,5 +1,5 @@
-SET @save_dbug = @@debug_dbug;
-set debug_dbug='+d,unstable_db_type';
+SET @saved_dbug = @@debug_dbug;
+SET debug_dbug='+d,unstable_db_type';
 install soname 'ha_archive';
 create table t1 (a int) engine=archive;
 insert t1 values (1),(2),(3);
@@ -33,4 +33,4 @@ t1.frm
 drop table t1;
 db.opt
 uninstall soname 'ha_archive';
-set debug_dbug=@save_dbug;
+SET debug_dbug=@saved_dbug;
diff --git a/mysql-test/main/drop_bad_db_type.test b/mysql-test/main/drop_bad_db_type.test
index 6a3ac6ae00f..ebc732104d3 100644
--- a/mysql-test/main/drop_bad_db_type.test
+++ b/mysql-test/main/drop_bad_db_type.test
@@ -7,8 +7,8 @@ if (!$HA_ARCHIVE_SO) {
 
 let $mysqld_datadir= `select @@datadir`;
 
-SET @save_dbug = @@debug_dbug;
-set debug_dbug='+d,unstable_db_type';
+SET @saved_dbug = @@debug_dbug;
+SET debug_dbug='+d,unstable_db_type';
 
 install soname 'ha_archive';
 create table t1 (a int) engine=archive;
@@ -28,4 +28,4 @@ drop table t1;
 --list_files $mysqld_datadir/test
 uninstall soname 'ha_archive';
 
-set debug_dbug=@save_dbug;
+SET debug_dbug=@saved_dbug;
diff --git a/mysql-test/main/engine_error_in_alter-8453.result b/mysql-test/main/engine_error_in_alter-8453.result
index c5a3375f33c..2c823f83038 100644
--- a/mysql-test/main/engine_error_in_alter-8453.result
+++ b/mysql-test/main/engine_error_in_alter-8453.result
@@ -1,6 +1,7 @@
 create table t1 (a int, b int);
-set debug_dbug='+d,external_lock_failure';
+SET @saved_dbug = @@SESSION.debug_dbug;
+SET debug_dbug='+d,external_lock_failure';
 alter table t1 add column c int;
 ERROR HY000: Got error 168 'KABOOM!' from MyISAM
-set debug_dbug='';
+SET debug_dbug= @saved_dbug;
 drop table t1;
diff --git a/mysql-test/main/engine_error_in_alter-8453.test b/mysql-test/main/engine_error_in_alter-8453.test
index c4600ec07fe..78e6de2d645 100644
--- a/mysql-test/main/engine_error_in_alter-8453.test
+++ b/mysql-test/main/engine_error_in_alter-8453.test
@@ -4,8 +4,9 @@
 --source include/have_debug.inc
 
 create table t1 (a int, b int);
-set debug_dbug='+d,external_lock_failure';
+SET @saved_dbug = @@SESSION.debug_dbug;
+SET debug_dbug='+d,external_lock_failure';
 --error ER_GET_ERRMSG
 alter table t1 add column c int;
-set debug_dbug='';
+SET debug_dbug= @saved_dbug;
 drop table t1;
diff --git a/mysql-test/main/error_simulation.result b/mysql-test/main/error_simulation.result
index 7e728d24fc8..457e5c8ec9c 100644
--- a/mysql-test/main/error_simulation.result
+++ b/mysql-test/main/error_simulation.result
@@ -10,6 +10,7 @@ INSERT INTO t1 VALUES
 ('AAAAAAAAAH','AAAAAAAAAH'), ('AAAAAAAAAI','AAAAAAAAAI'),
 ('AAAAAAAAAJ','AAAAAAAAAJ'), ('AAAAAAAAAK','AAAAAAAAAK');
 set tmp_table_size=1024;
+SET @saved_dbug = @@SESSION.debug_dbug;
 set session debug_dbug="+d,raise_error";
 SELECT MAX(a) FROM t1 GROUP BY a,b;
 ERROR 23000: Can't write; duplicate key in table '(temporary)'
@@ -22,7 +23,7 @@ CREATE TABLE t1 (a INT(100) NOT NULL);
 INSERT INTO t1 VALUES (1), (0), (2);
 SET SESSION debug_dbug='+d,alter_table_only_index_change';
 ALTER TABLE t1 ADD INDEX a(a);
-SET SESSION debug_dbug=DEFAULT;
+SET debug_dbug= @saved_dbug;
 SHOW CREATE TABLE t1;
 Table	Create Table
 t1	CREATE TABLE `t1` (
@@ -42,7 +43,7 @@ CREATE TABLE t1(a BLOB);
 SET SESSION debug_dbug="+d,bug42064_simulate_oom";
 INSERT INTO t1 VALUES("");
 Got one of the listed errors
-SET SESSION debug_dbug=DEFAULT;
+SET debug_dbug= @saved_dbug;
 DROP TABLE t1;
 #
 # Bug#41660: Sort-index_merge for non-first join table may require 
@@ -79,7 +80,7 @@ a	a	b	filler
 7	1	1	data
 8	1	1	data
 9	1	1	data
-SET SESSION debug_dbug= DEFAULT;
+SET debug_dbug= @saved_dbug;
 SET optimizer_switch=@save_optimizer_switch;
 DROP TABLE t1, t2;
 #
@@ -92,7 +93,7 @@ INSERT INTO t2 VALUES (1),(2);
 SET SESSION debug_dbug="+d,bug11747970_raise_error";
 INSERT IGNORE INTO t2 SELECT f1 FROM t1 a WHERE NOT EXISTS (SELECT 1 FROM t2 b WHERE a.f1 = b.f1);
 ERROR 70100: Query execution was interrupted
-SET SESSION debug_dbug = DEFAULT;
+SET debug_dbug= @saved_dbug;
 DROP TABLE t1,t2;
 #
 # End of 5.1 tests
@@ -126,4 +127,4 @@ SET SESSION debug_dbug="+d,simulate_create_virtual_tmp_table_out_of_memory";
 SELECT f1(1);
 Got one of the listed errors
 DROP FUNCTION f1;
-SET SESSION debug_dbug=DEFAULT;
+SET debug_dbug= @saved_dbug;
diff --git a/mysql-test/main/error_simulation.test b/mysql-test/main/error_simulation.test
index 1debed871c7..f713e2da6ba 100644
--- a/mysql-test/main/error_simulation.test
+++ b/mysql-test/main/error_simulation.test
@@ -21,6 +21,7 @@ set tmp_table_size=1024;
 
 # Set debug flag so an error is returned when
 # tmp table in query is converted from heap to myisam
+SET @saved_dbug = @@SESSION.debug_dbug;
 set session debug_dbug="+d,raise_error";
 
 --error ER_DUP_KEY
@@ -36,7 +37,7 @@ CREATE TABLE t1 (a INT(100) NOT NULL);
 INSERT INTO t1 VALUES (1), (0), (2);
 SET SESSION debug_dbug='+d,alter_table_only_index_change';
 ALTER TABLE t1 ADD INDEX a(a);
-SET SESSION debug_dbug=DEFAULT;
+SET debug_dbug= @saved_dbug;
 SHOW CREATE TABLE t1;
 SELECT * FROM t1;
 DROP TABLE t1;
@@ -51,7 +52,7 @@ SET SESSION debug_dbug="+d,bug42064_simulate_oom";
 # May fail with either ER_OUT_OF_RESOURCES or EE_OUTOFMEMORY
 --error ER_OUT_OF_RESOURCES, 5
 INSERT INTO t1 VALUES("");
-SET SESSION debug_dbug=DEFAULT;
+SET debug_dbug= @saved_dbug;
 
 DROP TABLE t1;
 
@@ -84,7 +85,7 @@ EXPLAIN
 SELECT * FROM t1 LEFT JOIN t2 ON ( t2.a < 10 OR t2.b < 10 );
 SELECT * FROM t1 LEFT JOIN t2 ON ( t2.a < 10 OR t2.b < 10 );
 
-SET SESSION debug_dbug= DEFAULT;
+SET debug_dbug= @saved_dbug;
 
 SET optimizer_switch=@save_optimizer_switch;
 
@@ -101,7 +102,7 @@ INSERT INTO t2 VALUES (1),(2);
 SET SESSION debug_dbug="+d,bug11747970_raise_error";
 --error ER_QUERY_INTERRUPTED
 INSERT IGNORE INTO t2 SELECT f1 FROM t1 a WHERE NOT EXISTS (SELECT 1 FROM t2 b WHERE a.f1 = b.f1);
-SET SESSION debug_dbug = DEFAULT;
+SET debug_dbug= @saved_dbug;
 DROP TABLE t1,t2;
 
 
@@ -156,4 +157,4 @@ SET SESSION debug_dbug="+d,simulate_create_virtual_tmp_table_out_of_memory";
 --error ER_OUT_OF_RESOURCES, 5
 SELECT f1(1);
 DROP FUNCTION f1;
-SET SESSION debug_dbug=DEFAULT;
+SET debug_dbug= @saved_dbug;
diff --git a/mysql-test/main/func_regexp_pcre_debug.result b/mysql-test/main/func_regexp_pcre_debug.result
index e44492fca72..40a379a077d 100644
--- a/mysql-test/main/func_regexp_pcre_debug.result
+++ b/mysql-test/main/func_regexp_pcre_debug.result
@@ -1,10 +1,9 @@
-SET debug_dbug='+d,pcre_exec_error_123';
+SET STATEMENT debug_dbug='+d,pcre_exec_error_123' for
 SELECT 'a' RLIKE 'a';
 'a' RLIKE 'a'
 0
 Warnings:
 Warning	1139	Got error 'pcre_exec: Internal error (-123)' from regexp
-SET debug_dbug='';
 SELECT 'a' RLIKE 'a';
 'a' RLIKE 'a'
 1
diff --git a/mysql-test/main/func_regexp_pcre_debug.test b/mysql-test/main/func_regexp_pcre_debug.test
index c2581fa4110..cbf5c4a17ee 100644
--- a/mysql-test/main/func_regexp_pcre_debug.test
+++ b/mysql-test/main/func_regexp_pcre_debug.test
@@ -1,6 +1,5 @@
 --source include/have_debug.inc
 
-SET debug_dbug='+d,pcre_exec_error_123';
+SET STATEMENT debug_dbug='+d,pcre_exec_error_123' for
 SELECT 'a' RLIKE 'a';
-SET debug_dbug='';
 SELECT 'a' RLIKE 'a';
diff --git a/mysql-test/main/log_slow_debug.result b/mysql-test/main/log_slow_debug.result
index 71a76342aba..16d67d7fdc7 100644
--- a/mysql-test/main/log_slow_debug.result
+++ b/mysql-test/main/log_slow_debug.result
@@ -6,7 +6,7 @@ SET @@GLOBAL.log_output='TABLE';
 FLUSH SLOW LOGS;
 SET @@GLOBAL.slow_query_log=ON;
 SET @@GLOBAL.log_slow_admin_statements=ON;
-SET @save_dbug = @@debug_dbug;
+SET @saved_dbug = @@debug_dbug;
 SET SESSION debug_dbug="+d,simulate_slow_query";
 CREATE PROCEDURE show_slow_log()
 BEGIN
@@ -218,7 +218,7 @@ sql_text
 #
 # Clean up
 #
-SET SESSION debug_dbug=@save_dbug;
+SET SESSION debug_dbug=@saved_dbug;
 TRUNCATE mysql.slow_log;
 SET @@global.slow_query_log= @org_slow_query_log;
 SET @@global.log_output= @org_log_output;
diff --git a/mysql-test/main/log_slow_debug.test b/mysql-test/main/log_slow_debug.test
index 6b7cdd62f8a..aba4cbc8dcb 100644
--- a/mysql-test/main/log_slow_debug.test
+++ b/mysql-test/main/log_slow_debug.test
@@ -9,7 +9,7 @@ SET @@GLOBAL.log_output='TABLE';
 FLUSH SLOW LOGS;
 SET @@GLOBAL.slow_query_log=ON;
 SET @@GLOBAL.log_slow_admin_statements=ON;
-SET @save_dbug = @@debug_dbug;
+SET @saved_dbug = @@debug_dbug;
 SET SESSION debug_dbug="+d,simulate_slow_query";
 
 DELIMITER $$;
@@ -87,7 +87,7 @@ CALL show_slow_log();
 --echo # Clean up
 --echo #
 
-SET SESSION debug_dbug=@save_dbug;
+SET SESSION debug_dbug=@saved_dbug;
 TRUNCATE mysql.slow_log;
 SET @@global.slow_query_log= @org_slow_query_log;
 SET @@global.log_output= @org_log_output;
diff --git a/mysql-test/main/mdev6830.result b/mysql-test/main/mdev6830.result
index d1cf8c98ac1..0048aa174bc 100644
--- a/mysql-test/main/mdev6830.result
+++ b/mysql-test/main/mdev6830.result
@@ -1,3 +1,4 @@
+SET @saved_dbug = @@SESSION.debug_dbug;
 set @@debug_dbug= 'd,opt';
 CREATE TABLE t1 (pk INT PRIMARY KEY) ENGINE=MyISAM;
 CREATE TABLE t2 (
@@ -46,3 +47,4 @@ SELECT * FROM t1, v3, t4 WHERE v3.f1 = t4.f1 AND t4.f2 = 6 AND t1.pk = v3.f5;
 pk	f1	f2	f3	f4	f5	f6	f7	f8	f9	f10	f11	f12	f13	f14	f15	f1	f2
 drop table t1,t2,t3,t4;
 drop view v2,v3;
+SET debug_dbug= @saved_dbug;
diff --git a/mysql-test/main/mdev6830.test b/mysql-test/main/mdev6830.test
index 3898d5bbef6..ab5f19f7093 100644
--- a/mysql-test/main/mdev6830.test
+++ b/mysql-test/main/mdev6830.test
@@ -2,7 +2,7 @@
 # MDEV-6830 Server crashes in best_access_path after a sequence of SELECTs invollving a temptable view
 #
 --source include/have_debug.inc
-
+SET @saved_dbug = @@SESSION.debug_dbug;
 set @@debug_dbug= 'd,opt';
 
 CREATE TABLE t1 (pk INT PRIMARY KEY) ENGINE=MyISAM;
@@ -60,4 +60,4 @@ SELECT * FROM t1, v3, t4 WHERE v3.f1 = t4.f1 AND t4.f2 = 6 AND t1.pk = v3.f5;
 
 drop table t1,t2,t3,t4;
 drop view v2,v3;
-
+SET debug_dbug= @saved_dbug;
diff --git a/mysql-test/main/merge-big.result b/mysql-test/main/merge-big.result
index 3b6e116986e..bd188d7a856 100644
--- a/mysql-test/main/merge-big.result
+++ b/mysql-test/main/merge-big.result
@@ -7,7 +7,7 @@ drop table if exists t1,t2,t3,t4,t5,t6;
 CREATE TABLE t1 (c1 INT) ENGINE= MyISAM;
 LOCK TABLE t1 WRITE;
 connect  con1,localhost,root,,;
-SET @orig_debug=@@debug;
+SET @orig_debug=@@global.debug_dbug;
 SET GLOBAL debug_dbug="+d,sleep_open_and_lock_after_open";
 INSERT INTO t1 VALUES (1);
 connection default;
diff --git a/mysql-test/main/merge-big.test b/mysql-test/main/merge-big.test
index 9bd2cab2c8a..5873d2eb233 100644
--- a/mysql-test/main/merge-big.test
+++ b/mysql-test/main/merge-big.test
@@ -42,7 +42,7 @@ LOCK TABLE t1 WRITE;
 #SELECT NOW();
     connect (con1,localhost,root,,);
     let $con1_id= `SELECT CONNECTION_ID()`;
-    SET @orig_debug=@@debug;
+    SET @orig_debug=@@global.debug_dbug;
     SET GLOBAL debug_dbug="+d,sleep_open_and_lock_after_open";
     send INSERT INTO t1 VALUES (1);
 connection default;
diff --git a/mysql-test/main/merge_debug.result b/mysql-test/main/merge_debug.result
index 51905e52d24..29858810ff1 100644
--- a/mysql-test/main/merge_debug.result
+++ b/mysql-test/main/merge_debug.result
@@ -3,7 +3,7 @@ set global storage_engine=myisam;
 set session storage_engine=myisam;
 call mtr.add_suppression("Index for table .*crashed' is corrupt; try to repair it");
 drop table if exists crashed,t2,t3,t4;
-SET @orig_debug=@@debug;
+SET @orig_debug=@@global.debug_dbug;
 CREATE TABLE crashed (c1 INT);
 CREATE TABLE t2 (c1 INT);
 CREATE TABLE t3 (c1 INT);
diff --git a/mysql-test/main/merge_debug.test b/mysql-test/main/merge_debug.test
index 3c617cfc545..50017bc1331 100644
--- a/mysql-test/main/merge_debug.test
+++ b/mysql-test/main/merge_debug.test
@@ -14,7 +14,7 @@ call mtr.add_suppression("Index for table .*crashed' is corrupt; try to repair i
 drop table if exists crashed,t2,t3,t4;
 --enable_warnings
 
-SET @orig_debug=@@debug;
+SET @orig_debug=@@global.debug_dbug;
 
 #
 # Check that MariaDB handles reopen that fails without crashing
diff --git a/mysql-test/main/myisam_debug.result b/mysql-test/main/myisam_debug.result
index 6232e3eac0e..1428473c850 100644
--- a/mysql-test/main/myisam_debug.result
+++ b/mysql-test/main/myisam_debug.result
@@ -34,10 +34,10 @@ create table t1 (a int, index(a));
 lock tables t1 write;
 insert t1 values (1),(2),(1);
 set @old_dbug=@@debug_dbug;
-set debug_dbug='+d,mi_lock_database_failure';
+SET debug_dbug='+d,mi_lock_database_failure';
 unlock tables;
 Warnings:
 Error	126	Index for table './test/t1.MYI' is corrupt; try to repair it
 Error	1030	Got error 22 "Invalid argument" from storage engine MyISAM
-set debug_dbug=@old_dbug;
+SET debug_dbug=@old_dbug;
 drop table t1;
diff --git a/mysql-test/main/myisam_debug.test b/mysql-test/main/myisam_debug.test
index 465ecd70895..2861c344b10 100644
--- a/mysql-test/main/myisam_debug.test
+++ b/mysql-test/main/myisam_debug.test
@@ -66,7 +66,7 @@ create table t1 (a int, index(a));
 lock tables t1 write;
 insert t1 values (1),(2),(1);
 set @old_dbug=@@debug_dbug;
-set debug_dbug='+d,mi_lock_database_failure';
+SET debug_dbug='+d,mi_lock_database_failure';
 unlock tables;
-set debug_dbug=@old_dbug;
+SET debug_dbug=@old_dbug;
 drop table t1;
diff --git a/mysql-test/main/range_innodb.result b/mysql-test/main/range_innodb.result
index 6572b248911..38a8964bb61 100644
--- a/mysql-test/main/range_innodb.result
+++ b/mysql-test/main/range_innodb.result
@@ -70,6 +70,7 @@ key(a),key(b),key(c)
 insert into t1
 select A.a+10*B.a, A.a+10*B.a, A.a+10*B.a+100*C.a
 from t0 A, t0 B, t0 C, t0 D where D.a<5;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set @@global.debug_dbug="+d,ha_index_init_fail";
 explain select * from t1 where a=10 and b=10;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
@@ -77,5 +78,5 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 select * from t1 where a=10 and b=10;
 ERROR HY000: Table definition has changed, please retry transaction
 DROP TABLE t0,t1;
-set @@global.debug_dbug="-d";
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 set @@optimizer_switch= @optimizer_switch_save;
diff --git a/mysql-test/main/range_innodb.test b/mysql-test/main/range_innodb.test
index a17ef3f1146..928ed74f784 100644
--- a/mysql-test/main/range_innodb.test
+++ b/mysql-test/main/range_innodb.test
@@ -80,10 +80,11 @@ create table t1 (
 insert into t1
 select A.a+10*B.a, A.a+10*B.a, A.a+10*B.a+100*C.a
 from t0 A, t0 B, t0 C, t0 D where D.a<5;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set @@global.debug_dbug="+d,ha_index_init_fail";
 explain select * from t1 where a=10 and b=10;
 --error ER_TABLE_DEF_CHANGED
 select * from t1 where a=10 and b=10;
 DROP TABLE t0,t1;
-set @@global.debug_dbug="-d";
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 set @@optimizer_switch= @optimizer_switch_save;
diff --git a/mysql-test/main/range_interrupted-13751.result b/mysql-test/main/range_interrupted-13751.result
index f4f995721ad..68610cdda8e 100644
--- a/mysql-test/main/range_interrupted-13751.result
+++ b/mysql-test/main/range_interrupted-13751.result
@@ -7,10 +7,10 @@ INSERT INTO t1 (c) SELECT c FROM t1;
 INSERT INTO t1 (c) SELECT c FROM t1;
 INSERT INTO t1 (c) SELECT c FROM t1;
 set @old_dbug=@@session.debug_dbug;
-set debug_dbug="+d,kill_join_init_read_record";
+SET debug_dbug="+d,kill_join_init_read_record";
 SELECT 1 FROM t1 AS alias1, t1 AS alias2, t1 AS alias3
 WHERE alias1.c = alias2.c OR alias1.i <= 1
 ;
 ERROR 70100: Query execution was interrupted
-set debug_dbug=@old_dbug;
+SET debug_dbug=@old_dbug;
 DROP TABLE t1;
diff --git a/mysql-test/main/range_interrupted-13751.test b/mysql-test/main/range_interrupted-13751.test
index 8b2c1834ee5..b0793edeb9d 100644
--- a/mysql-test/main/range_interrupted-13751.test
+++ b/mysql-test/main/range_interrupted-13751.test
@@ -14,14 +14,14 @@ INSERT INTO t1 (c) SELECT c FROM t1;
 INSERT INTO t1 (c) SELECT c FROM t1;
 
 set @old_dbug=@@session.debug_dbug;
-set debug_dbug="+d,kill_join_init_read_record";
+SET debug_dbug="+d,kill_join_init_read_record";
 
 --error ER_QUERY_INTERRUPTED
 SELECT 1 FROM t1 AS alias1, t1 AS alias2, t1 AS alias3
 WHERE alias1.c = alias2.c OR alias1.i <= 1
 ;
 
-set debug_dbug=@old_dbug;
+SET debug_dbug=@old_dbug;
 
 DROP TABLE t1;
 
diff --git a/mysql-test/main/select_debug.result b/mysql-test/main/select_debug.result
index 55882ad337a..dfe49aed215 100644
--- a/mysql-test/main/select_debug.result
+++ b/mysql-test/main/select_debug.result
@@ -6,6 +6,7 @@ insert into t1 values (2,2), (1,1);
 create table t2 (a int);
 insert into t2 values (2), (3);
 set session join_cache_level=3;
+SET @saved_dbug = @@SESSION.debug_dbug;
 set @@debug_dbug= 'd,opt';
 explain select t1.b from t1,t2 where t1.b=t2.a;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
@@ -16,3 +17,4 @@ b
 2
 set session join_cache_level=default;
 drop table t1,t2;
+SET debug_dbug= @saved_dbug;
diff --git a/mysql-test/main/select_debug.test b/mysql-test/main/select_debug.test
index 49415400db3..922cec7ed7a 100644
--- a/mysql-test/main/select_debug.test
+++ b/mysql-test/main/select_debug.test
@@ -10,6 +10,7 @@ create table t2 (a int);
 insert into t2 values (2), (3);
 
 set session join_cache_level=3;
+SET @saved_dbug = @@SESSION.debug_dbug;
 set @@debug_dbug= 'd,opt';
 
 explain select t1.b from t1,t2 where t1.b=t2.a;
@@ -17,3 +18,4 @@ select t1.b from t1,t2 where t1.b=t2.a;
 
 set session join_cache_level=default;
 drop table t1,t2;
+SET debug_dbug= @saved_dbug;
diff --git a/mysql-test/main/show_explain.result b/mysql-test/main/show_explain.result
index 0819ae5ba37..e280ae7040e 100644
--- a/mysql-test/main/show_explain.result
+++ b/mysql-test/main/show_explain.result
@@ -23,7 +23,7 @@ show explain for $thr1;
 ERROR HY000: Target is not running an EXPLAINable command
 connection con1;
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 select count(*) from t1 where a < 100000;
 connection default;
 show explain for $thr2;
@@ -58,10 +58,10 @@ connection con1;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	range	a	a	5	NULL	10	Using index condition; Rowid-ordered scan
 set optimizer_switch= @show_expl_tmp;
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 # UNION, first branch 
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 explain select a from t0 A union select a+1 from t0 B;
 connection default;
 show explain for $thr2;
@@ -76,10 +76,10 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	A	ALL	NULL	NULL	NULL	NULL	10	
 2	UNION	B	ALL	NULL	NULL	NULL	NULL	10	
 NULL	UNION RESULT	<union1,2>	ALL	NULL	NULL	NULL	NULL	NULL	
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 # UNION, second branch
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 explain select a from t0 A union select a+1 from t0 B;
 connection default;
 show explain for $thr2;
@@ -94,10 +94,10 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	A	ALL	NULL	NULL	NULL	NULL	10	
 2	UNION	B	ALL	NULL	NULL	NULL	NULL	10	
 NULL	UNION RESULT	<union1,2>	ALL	NULL	NULL	NULL	NULL	NULL	
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 # Uncorrelated  subquery, select
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 select a, (select max(a) from t0 B) from t0 A where a<1;
 connection default;
 show explain for $thr2;
@@ -109,10 +109,10 @@ Note	1003	select a, (select max(a) from t0 B) from t0 A where a<1
 connection con1;
 a	(select max(a) from t0 B)
 0	9
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 # Uncorrelated  subquery, explain
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 explain select a, (select max(a) from t0 B) from t0 A where a<1;
 connection default;
 show explain for $thr2;
@@ -125,10 +125,10 @@ connection con1;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	A	ALL	NULL	NULL	NULL	NULL	10	Using where
 2	SUBQUERY	B	ALL	NULL	NULL	NULL	NULL	10	
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 # correlated  subquery, select
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 select a, (select max(a) from t0 b where b.a+a.a<10) from t0 a where a<1;
 connection default;
 show explain for $thr2;
@@ -140,10 +140,10 @@ Note	1003	select a, (select max(a) from t0 b where b.a+a.a<10) from t0 a where a
 connection con1;
 a	(select max(a) from t0 b where b.a+a.a<10)
 0	9
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 # correlated  subquery, explain
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 select a, (select max(a) from t0 b where b.a+a.a<10) from t0 a where a<1;
 connection default;
 show explain for $thr2;
@@ -155,10 +155,10 @@ Note	1003	select a, (select max(a) from t0 b where b.a+a.a<10) from t0 a where a
 connection con1;
 a	(select max(a) from t0 b where b.a+a.a<10)
 0	9
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 # correlated  subquery, select, while inside the subquery
 set @show_explain_probe_select_id=2;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 select a, (select max(a) from t0 b where b.a+a.a<10) from t0 a where a<1;
 connection default;
 show explain for $thr2;
@@ -170,10 +170,10 @@ Note	1003	select a, (select max(a) from t0 b where b.a+a.a<10) from t0 a where a
 connection con1;
 a	(select max(a) from t0 b where b.a+a.a<10)
 0	9
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 # correlated  subquery, explain, while inside the subquery
 set @show_explain_probe_select_id=2;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 select a, (select max(a) from t0 b where b.a+a.a<10) from t0 a where a<1;
 connection default;
 show explain for $thr2;
@@ -185,10 +185,10 @@ Note	1003	select a, (select max(a) from t0 b where b.a+a.a<10) from t0 a where a
 connection con1;
 a	(select max(a) from t0 b where b.a+a.a<10)
 0	9
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 # correlated  subquery, explain, while inside the subquery
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_end';
+SET debug_dbug='+d,show_explain_probe_join_exec_end';
 select a, (select max(a) from t0 b where b.a+a.a<10) from t0 a where a<1;
 connection default;
 show explain for $thr2;
@@ -200,12 +200,12 @@ Note	1003	select a, (select max(a) from t0 b where b.a+a.a<10) from t0 a where a
 connection con1;
 a	(select max(a) from t0 b where b.a+a.a<10)
 0	9
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 # Try to do SHOW EXPLAIN for a query that runs a  SET command:
 #   I've found experimentally that select_id==2 here...
 # 
 set @show_explain_probe_select_id=2;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 set @foo= (select max(a) from t0 where sin(a) >0);
 connection default;
 show explain for $thr2;
@@ -213,13 +213,13 @@ ERROR HY000: Target is not running an EXPLAINable command
 kill query $thr2;
 connection con1;
 ERROR 70100: Query execution was interrupted
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 #
 # Attempt SHOW EXPLAIN for an UPDATE
 #
 create table t2 as select a as a, a as dummy from t0 limit 2;
 set @show_explain_probe_select_id=2;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 update t2 set dummy=0 where (select max(a) from t0 where t2.a + t0.a <3) >3 ;
 connection default;
 show explain for $thr2;
@@ -236,13 +236,13 @@ Warnings:
 Note	1003	update t2 set dummy=0 where (select max(a) from t0 where t2.a + t0.a <3) >3
 connection con1;
 drop table t2;
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 #
 # Attempt SHOW EXPLAIN for a DELETE (UPD: now works)
 # 
 create table t2 as select a as a, a as dummy from t0 limit 2;
 set @show_explain_probe_select_id=2;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 delete from t2 where (select max(a) from t0 where t2.a + t0.a <3) >3 ;
 connection default;
 show explain for $thr2;
@@ -259,13 +259,13 @@ Warnings:
 Note	1003	delete from t2 where (select max(a) from t0 where t2.a + t0.a <3) >3
 connection con1;
 drop table t2;
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 #
 # Multiple SHOW EXPLAIN calls for one select 
 # 
 create table t2 as select a as a, a as dummy from t0 limit 3;
 set @show_explain_probe_select_id=2;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 select t2.a, ((select max(a) from t0 where t2.a + t0.a <3) >3) as SUBQ from t2;
 connection default;
 show explain for $thr2;
@@ -292,14 +292,14 @@ a	SUBQ
 1	0
 2	0
 drop table t2;
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 #
 # SHOW EXPLAIN for SELECT ... ORDER BY with "Using filesort"
 #
 explain select * from t0 order by a;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t0	ALL	NULL	NULL	NULL	NULL	10	Using filesort
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 set @show_explain_probe_select_id=1;
 select * from t0 order by a;
 connection default;
@@ -320,7 +320,7 @@ a
 7
 8
 9
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 #
 # SHOW EXPLAIN for SELECT ... with "Using temporary"
 #
@@ -329,7 +329,7 @@ explain select distinct a from t0;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t0	ALL	NULL	NULL	NULL	NULL	10	Using temporary
 connection con1;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 set @show_explain_probe_select_id=1;
 select distinct a from t0;
 connection default;
@@ -350,7 +350,7 @@ a
 7
 8
 9
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 #
 # SHOW EXPLAIN for SELECT ... with "Using temporary; Using filesort"
 #
@@ -359,7 +359,7 @@ explain select distinct a from t0;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t0	ALL	NULL	NULL	NULL	NULL	10	Using temporary
 connection con1;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 set @show_explain_probe_select_id=1;
 select distinct a from t0;
 connection default;
@@ -380,7 +380,7 @@ a
 7
 8
 9
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 #
 # MDEV-238: SHOW EXPLAIN: Server crashes in JOIN::print_explain with FROM subquery and GROUP BY
 #
@@ -390,7 +390,7 @@ explain SELECT alias.a FROM t2, ( SELECT * FROM t2 ) AS alias GROUP BY alias.a;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	5	Using temporary; Using filesort
 1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	5	Using join buffer (flat, BNL join)
-set debug_dbug='+d,show_explain_in_find_all_keys';
+SET debug_dbug='+d,show_explain_in_find_all_keys';
 SELECT alias.a FROM t2, ( SELECT * FROM t2 ) AS alias GROUP BY alias.a;
 connection default;
 # FIXED by "conservative assumptions about when QEP is available" fix:
@@ -406,7 +406,7 @@ a
 1
 2
 4
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 DROP TABLE t2;
 #
 # MDEV-239: Assertion `field_types == 0 ... ' failed in Protocol_text::store(double, uint32, String*) with 
@@ -421,7 +421,7 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 Warnings:
 Note	1003	select `test`.`t2`.`a` AS `a` from `test`.`t2` join `test`.`t2` group by `test`.`t2`.`a`
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_end';
+SET debug_dbug='+d,show_explain_probe_join_exec_end';
 EXPLAIN EXTENDED SELECT alias.a FROM t2, ( SELECT * FROM t2 ) AS alias GROUP BY alias.a ;
 connection default;
 show explain for $thr2;
@@ -436,7 +436,7 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	5	100.00	Using join buffer (flat, BNL join)
 Warnings:
 Note	1003	select `test`.`t2`.`a` AS `a` from `test`.`t2` join `test`.`t2` group by `test`.`t2`.`a`
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 DROP TABLE t2;
 #
 # MDEV-240: SHOW EXPLAIN: Assertion `this->optimized == 2' failed in 
@@ -453,7 +453,7 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	t2	ALL	NULL	NULL	NULL	NULL	6	
 2	DERIVED	t3	system	NULL	NULL	NULL	NULL	1	
 set @show_explain_probe_select_id=2;
-set debug_dbug='+d,show_explain_probe_join_exec_end';
+SET debug_dbug='+d,show_explain_probe_join_exec_end';
 SELECT * FROM v1, t2;
 connection default;
 show explain for $thr2;
@@ -461,14 +461,14 @@ ERROR HY000: Target is not running an EXPLAINable command
 kill query $thr2;
 connection con1;
 ERROR 70100: Query execution was interrupted
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 DROP VIEW v1;
 DROP TABLE t2, t3;
 #
 # MDEV-267: SHOW EXPLAIN: Server crashes in JOIN::print_explain on most of queries
 #
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_end';
+SET debug_dbug='+d,show_explain_probe_join_exec_end';
 select sleep(1);
 connection default;
 show explain for $thr2;
@@ -479,12 +479,12 @@ Note	1003	select sleep(1)
 connection con1;
 sleep(1)
 0
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 #
 # Same as above, but try another reason for JOIN to be degenerate
 #
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_end';
+SET debug_dbug='+d,show_explain_probe_join_exec_end';
 select * from t0 where 1>10;
 connection default;
 show explain for $thr2;
@@ -494,14 +494,14 @@ Warnings:
 Note	1003	select * from t0 where 1>10
 connection con1;
 a
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 #
 # Same as above, but try another reason for JOIN to be degenerate (2)
 #
 create table t3(a int primary key);
 insert into t3 select a from t0;
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_end';
+SET debug_dbug='+d,show_explain_probe_join_exec_end';
 select * from t0,t3 where t3.a=112233;
 connection default;
 show explain for $thr2;
@@ -511,7 +511,7 @@ Warnings:
 Note	1003	select * from t0,t3 where t3.a=112233
 connection con1;
 a	a
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 drop table t3;
 #
 # MDEV-270: SHOW EXPLAIN: server crashes in JOIN::print_explain on a query with 
@@ -530,7 +530,7 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 2	SUBQUERY	t2	const	PRIMARY	PRIMARY	4	const	1	
 3	SUBQUERY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Select tables optimized away
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_do_select';
+SET debug_dbug='+d,show_explain_probe_do_select';
 SELECT * FROM t2 WHERE a = 
 (SELECT MAX(a) FROM t2 
 WHERE pk= (SELECT MAX(pk) FROM t2 WHERE pk = 3)
@@ -552,7 +552,7 @@ pk	a
 6	7
 7	7
 9	7
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 drop table t2;
 #
 # MDEV-273: SHOW EXPLAIN: server crashes in JOIN::print_explain on a query with impossible WHERE
@@ -584,7 +584,7 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	t3	ALL	NULL	NULL	NULL	NULL	87	Using join buffer (flat, BNL join)
 2	SUBQUERY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Impossible WHERE noticed after reading const tables
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_do_select';
+SET debug_dbug='+d,show_explain_probe_do_select';
 SELECT count(*) FROM t2, t3
 WHERE a1 < ALL ( 
 SELECT a1 FROM t2
@@ -605,7 +605,7 @@ WHERE a1 IN ( SELECT a1 FROM t2, t4 )
 connection con1;
 count(*)
 1740
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 drop table t2, t3, t4;
 #
 # MDEV-275: SHOW EXPLAIN: server crashes in JOIN::print_explain with IN subquery and aggregate function
@@ -615,7 +615,7 @@ INSERT INTO t2 VALUES
 (1,5),(2,4),(3,6),(4,9),(5,2),(6,8),(7,4),(8,8),(9,0),(10,43),
 (11,23),(12,3),(13,45),(14,16),(15,2),(16,33),(17,2),(18,5),(19,9),(20,2);
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_end';
+SET debug_dbug='+d,show_explain_probe_join_exec_end';
 SELECT * FROM t2 WHERE (5, 78) IN (SELECT `a1`, MAX(`a1`) FROM t2 GROUP BY `a1`);
 connection default;
 show explain for $thr2;
@@ -627,7 +627,7 @@ Warnings:
 Note	1003	SELECT * FROM t2 WHERE (5, 78) IN (SELECT `a1`, MAX(`a1`) FROM t2 GROUP BY `a1`)
 connection con1;
 pk	a1
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 DROP TABLE t2;
 DROP TABLE t1;
 #
@@ -636,7 +636,7 @@ DROP TABLE t1;
 CREATE TABLE t1(a INT, KEY(a));
 INSERT INTO t1 VALUES (3),(1),(5),(1);
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 SELECT 'test' FROM t1 WHERE a=1;
 connection default;
 show explain for $thr2;
@@ -648,7 +648,7 @@ connection con1;
 test
 test
 test
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 DROP TABLE t1;
 #
 # MDEV-299: SHOW EXPLAIN: Plan produced by SHOW EXPLAIN changes back and forth during query execution
@@ -666,7 +666,7 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	A	ALL	NULL	NULL	NULL	NULL	100	Using where
 1	SIMPLE	B	ALL	key1	NULL	NULL	NULL	100	Range checked for each record (index map: 0x1)
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_test_if_quick_select';
+SET debug_dbug='+d,show_explain_probe_test_if_quick_select';
 select count(*) from t1 A, t1 B where B.key1 < A.col2 and A.col1=3 AND B.col2 + 1 < 100;
 connection default;
 show explain for $thr2;
@@ -696,7 +696,7 @@ Note	1003	select count(*) from t1 A, t1 B where B.key1 < A.col2 and A.col1=3 AND
 connection con1;
 count(*)
 212
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 drop table t1;
 #
 # MDEV-297: SHOW EXPLAIN: Server gets stuck until timeout occurs while
@@ -705,7 +705,7 @@ drop table t1;
 CREATE TABLE t1(a INT, b INT, c INT, KEY(a), KEY(b), KEY(c));
 INSERT INTO t1 (a) VALUES (3),(1),(5),(1);
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 SHOW INDEX FROM t1;
 connection default;
 show explain for $thr2;
@@ -718,7 +718,7 @@ Table	Non_unique	Key_name	Seq_in_index	Column_name	Collation	Cardinality	Sub_par
 t1	1	a	1	a	A	NULL	NULL	NULL	YES	BTREE		
 t1	1	b	1	b	A	NULL	NULL	NULL	YES	BTREE		
 t1	1	c	1	c	A	NULL	NULL	NULL	YES	BTREE		
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 DROP TABLE t1;
 #
 # MDEV-324: SHOW EXPLAIN: Plan produced by SHOW EXPLAIN for a query with TEMPTABLE view 
@@ -731,7 +731,7 @@ EXPLAIN SELECT a + 1 FROM v1;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	<derived2>	ALL	NULL	NULL	NULL	NULL	2	
 2	DERIVED	t1	ALL	NULL	NULL	NULL	NULL	2	
-set debug_dbug='+d,show_explain_probe_join_tab_preread';
+SET debug_dbug='+d,show_explain_probe_join_tab_preread';
 set @show_explain_probe_select_id=1;
 SELECT a + 1 FROM v1;
 connection default;
@@ -745,7 +745,7 @@ connection con1;
 a + 1
 2
 3
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 DROP VIEW v1;
 DROP TABLE t1;
 #
@@ -761,7 +761,7 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 2	DEPENDENT SUBQUERY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	No tables used
 3	DEPENDENT UNION	NULL	NULL	NULL	NULL	NULL	NULL	NULL	No tables used
 NULL	UNION RESULT	<union2,3>	ALL	NULL	NULL	NULL	NULL	NULL	
-set debug_dbug='+d,show_explain_probe_union_read';
+SET debug_dbug='+d,show_explain_probe_union_read';
 SELECT a FROM t1 WHERE a IN ( SELECT 1+SLEEP(0.01) UNION SELECT 2 );
 connection default;
 show explain for $thr2;
@@ -782,7 +782,7 @@ Warnings:
 Note	1003	SELECT a FROM t1 WHERE a IN ( SELECT 1+SLEEP(0.01) UNION SELECT 2 )
 connection con1;
 a
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 DROP TABLE t1;
 #
 # MDEV-327: SHOW EXPLAIN: Different select_type in plans produced by SHOW EXPLAIN 
@@ -805,7 +805,7 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 3	SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	20	
 3	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	20	Using where
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 SELECT * FROM t1, ( SELECT * FROM t2 ) AS alias
 WHERE a < ALL ( SELECT b FROM t1, t2 WHERE a = b );
 connection default;
@@ -820,7 +820,7 @@ Note	1003	SELECT * FROM t1, ( SELECT * FROM t2 ) AS alias
 WHERE a < ALL ( SELECT b FROM t1, t2 WHERE a = b )
 connection con1;
 a	b
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 DROP TABLE t1, t2;
 # 
 #  Test that SHOW EXPLAIN will print 'Distinct'.
@@ -842,7 +842,7 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	index	PRIMARY	PRIMARY	4	NULL	4	Using index; Using temporary
 1	SIMPLE	t3	ref	a	a	5	test.t1.a	7	Using index; Distinct
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 select distinct t1.a from t1,t3 where t1.a=t3.a;
 connection default;
 show explain for $thr2;
@@ -855,7 +855,7 @@ connection con1;
 a
 1
 2
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 drop table t1,t3,t4;
 #
 # ----------  SHOW EXPLAIN and permissions -----------------
@@ -869,7 +869,7 @@ connection con1;
 #  First, make sure that user 'test2' cannot do SHOW EXPLAIN on us
 #
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 select * from t0 where a < 3;
 connection default;
 connection con2;
@@ -886,14 +886,14 @@ a
 0
 1
 2
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 #
 # Check that user test2 can do SHOW EXPLAIN on its own queries 
 #
 connect  con3, localhost, test2,,;
 connection con2;
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 select * from t0 where a < 3;
 connection con1;
 connection con3;
@@ -916,9 +916,9 @@ disconnect con2;
 grant process on *.* to test2@localhost;
 connect  con2, localhost, test2,,;
 connection con1;
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 select * from t0 where a < 3;
 connection default;
 connection con2;
@@ -932,7 +932,7 @@ a
 0
 1
 2
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 revoke all privileges on test.* from test2@localhost;
 drop user test2@localhost;
 disconnect con2;
@@ -1009,7 +1009,7 @@ ORDER BY b;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	index_merge	a,b	a,b	5,5	NULL	8	Using sort_union(a,b); Using where; Using filesort
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 SELECT a+SLEEP(0.01) FROM t1
 WHERE a IN ( 255, 0 ) OR b BETWEEN 6 AND 129
 ORDER BY b;
@@ -1030,9 +1030,9 @@ a+SLEEP(0.01)
 0
 0
 0
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_do_select';
+SET debug_dbug='+d,show_explain_probe_do_select';
 SELECT a+SLEEP(0.01) FROM t1
 WHERE a IN ( 255, 0 ) OR b BETWEEN 6 AND 129
 ORDER BY b;
@@ -1053,7 +1053,7 @@ a+SLEEP(0.01)
 0
 0
 0
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 drop table t1;
 # 
 # MDEV-298: SHOW EXPLAIN: Plan returned by SHOW EXPLAIN only contains 
@@ -1067,7 +1067,7 @@ EXPLAIN SELECT a FROM t1 GROUP BY a;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	4112	Using temporary; Using filesort
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 SELECT a FROM t1 GROUP BY a;
 connection default;
 show explain for $thr2;
@@ -1093,7 +1093,7 @@ a
 14
 15
 16
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 drop table t1;
 #
 # MDEV-408: SHOW EXPLAIN: Some values are chopped off in SHOW EXPLAIN output
@@ -1107,7 +1107,7 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	2	Using where
 2	DEPENDENT SUBQUERY	t2	index_subquery	PRIMARY,c	c	5	func	1	Using index; Using where
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 SELECT SUM(a + SLEEP(0.1)) FROM t1 WHERE a IN ( SELECT c FROM t2 WHERE d < b ) OR b < 's';
 connection default;
 show explain for $thr2;
@@ -1119,7 +1119,7 @@ Note	1003	SELECT SUM(a + SLEEP(0.1)) FROM t1 WHERE a IN ( SELECT c FROM t2 WHERE
 connection con1;
 SUM(a + SLEEP(0.1))
 7862
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 drop table t1, t2;
 #
 # MDEV-412: SHOW EXPLAIN: Server crashes in JOIN::print_explain on a query with inner join and ORDER BY the same column twice
@@ -1157,7 +1157,7 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	range	b	b	6	NULL	107	Using where; Using index
 1	SIMPLE	t3	ref	PRIMARY	PRIMARY	5	test.t1.b	1	Using index
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_do_select';
+SET debug_dbug='+d,show_explain_probe_do_select';
 SELECT b AS field1, b AS field2 FROM t1, t2, t3 WHERE d = b ORDER BY field1, field2;
 connection default;
 show explain for $thr2;
@@ -1169,7 +1169,7 @@ Warnings:
 Note	1003	SELECT b AS field1, b AS field2 FROM t1, t2, t3 WHERE d = b ORDER BY field1, field2
 connection con1;
 field1	field2
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 DROP TABLE t1,t2,t3;
 #
 # MDEV-423: SHOW EXPLAIN: 'Using where' for a subquery is shown in EXPLAIN, but not in SHOW EXPLAIN output
@@ -1190,7 +1190,7 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	t2	ALL	NULL	NULL	NULL	NULL	20	
 3	SUBQUERY	t3	ALL	NULL	NULL	NULL	NULL	20	Using where
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 SELECT max(a+b+c) FROM t1 AS alias1, ( SELECT * FROM t2 ) AS alias 
 WHERE EXISTS ( SELECT * FROM t3 WHERE b = c )  OR a <= 10;
 connection default;
@@ -1205,7 +1205,7 @@ WHERE EXISTS ( SELECT * FROM t3 WHERE b = c )  OR a <= 10
 connection con1;
 max(a+b+c)
 279
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 DROP TABLE t1,t2,t3;
 #
 # MDEV-416: Server crashes in SQL_SELECT::cleanup on EXPLAIN with SUM ( DISTINCT ) in a non-correlated subquery (5.5-show-explain tree)
@@ -1231,7 +1231,7 @@ select hex('��');
 hex('��')
 E3FB
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 select * from t0 where length('��') = a;
 connection default;
 set names utf8;
@@ -1244,7 +1244,7 @@ set names default;
 connection con1;
 a
 2
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 set names default;
 #
 # MDEV-462: SHOW EXPLAIN: Assertion `table_list->table' fails in find_field_in_table_ref if FOR contains a non-numeric value
@@ -1270,7 +1270,7 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 3	DEPENDENT SUBQUERY	t1	ALL	a	NULL	NULL	NULL	2	Range checked for each record (index map: 0x1)
 4	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	2	
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 SELECT SUM(b) FROM ( SELECT * FROM t1 ) AS alias1, t2 
 WHERE b <= ANY ( 
 SELECT a FROM t1 
@@ -1290,7 +1290,7 @@ WHERE a = b + SLEEP(0.2) OR a >= ( SELECT SUM(b) FROM t2 ))
 connection con1;
 SUM(b)
 0
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 DROP TABLE t1,t2;
 drop table t0;
 #
@@ -1302,7 +1302,7 @@ create table t1 (a int, b int);
 insert into t1 select a,a from t0;
 create table t2 as select * from t1;
 set @show_explain_probe_select_id=2;
-set debug_dbug='+d,show_explain_probe_best_ext_lim_search';
+SET debug_dbug='+d,show_explain_probe_best_ext_lim_search';
 explain 
 select * from t0 
 where not exists ( select 1 from t1, t2 where t1.b=t2.b and t2.a=t0.a) and a is null;
diff --git a/mysql-test/main/show_explain.test b/mysql-test/main/show_explain.test
index 6615ff66737..2a87d24cf6d 100644
--- a/mysql-test/main/show_explain.test
+++ b/mysql-test/main/show_explain.test
@@ -15,7 +15,7 @@ SET @old_debug= @@session.debug;
 # is that we use the following commands for synchronization:
 #
 #    set @show_explain_probe_select_id=1;
-#    set debug_dbug='d,show_explain_probe_join_exec_start';
+#    SET debug_dbug='d,show_explain_probe_join_exec_start';
 #    send select count(*) from t1 where a < 100000;
 #
 # When ran with mysqltest_embedded, this translates into: 
@@ -75,7 +75,7 @@ let $wait_condition= select State='show_explain_trap' from information_schema.pr
 #
 connection con1;
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 send select count(*) from t1 where a < 100000;
 
 connection default;
@@ -103,109 +103,109 @@ evalp show explain for $thr2;
 connection con1;
 reap;
 set optimizer_switch= @show_expl_tmp;
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 
 --echo # UNION, first branch 
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 send explain select a from t0 A union select a+1 from t0 B;
 connection default;
 --source include/wait_condition.inc
 evalp show explain for $thr2;
 connection con1;
 reap;
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 
 
 --echo # UNION, second branch
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 send explain select a from t0 A union select a+1 from t0 B;
 connection default;
 --source include/wait_condition.inc
 evalp show explain for $thr2;
 connection con1;
 reap;
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 
 
 --echo # Uncorrelated  subquery, select
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 send select a, (select max(a) from t0 B) from t0 A where a<1;
 connection default;
 --source include/wait_condition.inc
 evalp show explain for $thr2;
 connection con1;
 reap;
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 
 
 --echo # Uncorrelated  subquery, explain
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 send explain select a, (select max(a) from t0 B) from t0 A where a<1;
 connection default;
 --source include/wait_condition.inc
 evalp show explain for $thr2;
 connection con1;
 reap;
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 
 --echo # correlated  subquery, select
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 send select a, (select max(a) from t0 b where b.a+a.a<10) from t0 a where a<1;
 connection default;
 --source include/wait_condition.inc
 evalp show explain for $thr2;
 connection con1;
 reap;
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 
 --echo # correlated  subquery, explain
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 send select a, (select max(a) from t0 b where b.a+a.a<10) from t0 a where a<1;
 connection default;
 --source include/wait_condition.inc
 evalp show explain for $thr2;
 connection con1;
 reap;
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 
 --echo # correlated  subquery, select, while inside the subquery
 set @show_explain_probe_select_id=2; # <---
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 send select a, (select max(a) from t0 b where b.a+a.a<10) from t0 a where a<1;
 connection default;
 --source include/wait_condition.inc
 evalp show explain for $thr2;
 connection con1;
 reap;
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 
 --echo # correlated  subquery, explain, while inside the subquery
 set @show_explain_probe_select_id=2;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 send select a, (select max(a) from t0 b where b.a+a.a<10) from t0 a where a<1;
 connection default;
 --source include/wait_condition.inc
 evalp show explain for $thr2;
 connection con1;
 reap;
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 
 --echo # correlated  subquery, explain, while inside the subquery
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_end';
+SET debug_dbug='+d,show_explain_probe_join_exec_end';
 send select a, (select max(a) from t0 b where b.a+a.a<10) from t0 a where a<1;
 connection default;
 --source include/wait_condition.inc
 evalp show explain for $thr2;
 connection con1;
 reap;
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 
 # TODO: explain in the parent subuqery when the un-correlated child has been
 # run (and have done irreversible cleanups)
@@ -218,7 +218,7 @@ set debug_dbug=@old_debug;
 --echo #   I've found experimentally that select_id==2 here...
 --echo # 
 set @show_explain_probe_select_id=2;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 send set @foo= (select max(a) from t0 where sin(a) >0);
 connection default;
 --source include/wait_condition.inc
@@ -228,14 +228,14 @@ evalp kill query $thr2;
 connection con1;
 --error ER_QUERY_INTERRUPTED
 reap;
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 
 --echo #
 --echo # Attempt SHOW EXPLAIN for an UPDATE
 --echo #
 create table t2 as select a as a, a as dummy from t0 limit 2;
 set @show_explain_probe_select_id=2;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 send update t2 set dummy=0 where (select max(a) from t0 where t2.a + t0.a <3) >3 ;
 connection default;
 --source include/wait_condition.inc
@@ -247,14 +247,14 @@ evalp show explain for $thr2;
 connection con1;
 reap;
 drop table t2;
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 
 --echo #
 --echo # Attempt SHOW EXPLAIN for a DELETE (UPD: now works)
 --echo # 
 create table t2 as select a as a, a as dummy from t0 limit 2;
 set @show_explain_probe_select_id=2;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 send delete from t2 where (select max(a) from t0 where t2.a + t0.a <3) >3 ;
 connection default;
 --source include/wait_condition.inc
@@ -266,14 +266,14 @@ evalp show explain for $thr2;
 connection con1;
 reap;
 drop table t2;
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 
 --echo #
 --echo # Multiple SHOW EXPLAIN calls for one select 
 --echo # 
 create table t2 as select a as a, a as dummy from t0 limit 3;
 set @show_explain_probe_select_id=2;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 send select t2.a, ((select max(a) from t0 where t2.a + t0.a <3) >3) as SUBQ from t2;
 connection default;
 --source include/wait_condition.inc
@@ -285,14 +285,14 @@ evalp show explain for $thr2;
 connection con1;
 reap;
 drop table t2;
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 
 --echo #
 --echo # SHOW EXPLAIN for SELECT ... ORDER BY with "Using filesort"
 --echo #
 explain select * from t0 order by a;
 
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 set @show_explain_probe_select_id=1;
 send select * from t0 order by a; 
 connection default;
@@ -300,7 +300,7 @@ connection default;
 evalp show explain for $thr2;
 connection con1;
 reap;
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 
 --echo #
 --echo # SHOW EXPLAIN for SELECT ... with "Using temporary"
@@ -309,7 +309,7 @@ connection default;
 explain select distinct a from t0;
 connection con1;
 
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 set @show_explain_probe_select_id=1;
 send select distinct a from t0; 
 connection default;
@@ -317,7 +317,7 @@ connection default;
 evalp show explain for $thr2;
 connection con1;
 reap;
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 
 --echo #
 --echo # SHOW EXPLAIN for SELECT ... with "Using temporary; Using filesort"
@@ -326,7 +326,7 @@ connection default;
 explain select distinct a from t0;
 connection con1;
 
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 set @show_explain_probe_select_id=1;
 send select distinct a from t0; 
 connection default;
@@ -334,7 +334,7 @@ connection default;
 evalp show explain for $thr2;
 connection con1;
 reap;
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 
 --echo #
 --echo # MDEV-238: SHOW EXPLAIN: Server crashes in JOIN::print_explain with FROM subquery and GROUP BY
@@ -343,7 +343,7 @@ CREATE TABLE t2 ( a INT );
 INSERT INTO t2 VALUES (1),(2),(1),(4),(2);
 explain SELECT alias.a FROM t2, ( SELECT * FROM t2 ) AS alias GROUP BY alias.a;
 
-set debug_dbug='+d,show_explain_in_find_all_keys';
+SET debug_dbug='+d,show_explain_in_find_all_keys';
 send SELECT alias.a FROM t2, ( SELECT * FROM t2 ) AS alias GROUP BY alias.a;
 
 connection default;
@@ -354,7 +354,7 @@ connection default;
 evalp show explain for $thr2;
 connection con1;
 reap;
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 DROP TABLE t2;
 
 
@@ -370,7 +370,7 @@ INSERT INTO t2 VALUES (1),(2),(1),(4),(2);
 EXPLAIN EXTENDED SELECT alias.a FROM t2, ( SELECT * FROM t2 ) AS alias GROUP BY alias.a ;
 
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_end';
+SET debug_dbug='+d,show_explain_probe_join_exec_end';
 send EXPLAIN EXTENDED SELECT alias.a FROM t2, ( SELECT * FROM t2 ) AS alias GROUP BY alias.a ;
 
 connection default;
@@ -378,7 +378,7 @@ connection default;
 evalp show explain for $thr2;
 connection con1;
 reap;
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 DROP TABLE t2;
 
 
@@ -394,7 +394,7 @@ INSERT INTO t2 VALUES (4),(5),(6),(7),(8),(9);
 explain SELECT * FROM v1, t2;
 
 set @show_explain_probe_select_id=2;
-set debug_dbug='+d,show_explain_probe_join_exec_end';
+SET debug_dbug='+d,show_explain_probe_join_exec_end';
 send SELECT * FROM v1, t2;
 
 connection default;
@@ -405,7 +405,7 @@ evalp kill query $thr2;
 connection con1;
 --error ER_QUERY_INTERRUPTED
 reap;
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 DROP VIEW v1;
 DROP TABLE t2, t3;
 
@@ -413,21 +413,21 @@ DROP TABLE t2, t3;
 --echo # MDEV-267: SHOW EXPLAIN: Server crashes in JOIN::print_explain on most of queries
 --echo #
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_end';
+SET debug_dbug='+d,show_explain_probe_join_exec_end';
 send select sleep(1);
 connection default;
 --source include/wait_condition.inc
 evalp show explain for $thr2;
 connection con1;
 reap;
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 
 
 --echo #
 --echo # Same as above, but try another reason for JOIN to be degenerate
 --echo #
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_end';
+SET debug_dbug='+d,show_explain_probe_join_exec_end';
 send select * from t0 where 1>10;
 connection default;
 --source include/wait_condition.inc
@@ -435,7 +435,7 @@ connection default;
 evalp show explain for $thr2;
 connection con1;
 reap;
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 
 --echo #
 --echo # Same as above, but try another reason for JOIN to be degenerate (2)
@@ -443,7 +443,7 @@ set debug_dbug=@old_debug;
 create table t3(a int primary key);
 insert into t3 select a from t0;
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_end';
+SET debug_dbug='+d,show_explain_probe_join_exec_end';
 send select * from t0,t3 where t3.a=112233;
 connection default;
 --source include/wait_condition.inc
@@ -451,7 +451,7 @@ connection default;
 evalp show explain for $thr2;
 connection con1;
 reap;
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 drop table t3;
 
 --echo #
@@ -470,7 +470,7 @@ explain SELECT * FROM t2 WHERE a =
        );
 
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_do_select';
+SET debug_dbug='+d,show_explain_probe_do_select';
 send SELECT * FROM t2 WHERE a = 
        (SELECT MAX(a) FROM t2 
         WHERE pk= (SELECT MAX(pk) FROM t2 WHERE pk = 3)
@@ -480,7 +480,7 @@ connection default;
 evalp show explain for $thr2;
 connection con1;
 reap;
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 drop table t2;
 
 
@@ -513,7 +513,7 @@ WHERE a1 < ALL (
 );
 
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_do_select';
+SET debug_dbug='+d,show_explain_probe_do_select';
 send
 SELECT count(*) FROM t2, t3
 WHERE a1 < ALL ( 
@@ -526,7 +526,7 @@ connection default;
 evalp show explain for $thr2;
 connection con1;
 reap;
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 drop table t2, t3, t4;
 
 --echo #
@@ -538,7 +538,7 @@ INSERT INTO t2 VALUES
   (11,23),(12,3),(13,45),(14,16),(15,2),(16,33),(17,2),(18,5),(19,9),(20,2);
 
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_end';
+SET debug_dbug='+d,show_explain_probe_join_exec_end';
 send
   SELECT * FROM t2 WHERE (5, 78) IN (SELECT `a1`, MAX(`a1`) FROM t2 GROUP BY `a1`);
 connection default;
@@ -547,7 +547,7 @@ connection default;
 evalp show explain for $thr2;
 connection con1;
 reap;
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 
 DROP TABLE t2;
 DROP TABLE t1;
@@ -559,7 +559,7 @@ CREATE TABLE t1(a INT, KEY(a));
 INSERT INTO t1 VALUES (3),(1),(5),(1);
 
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 
 send SELECT 'test' FROM t1 WHERE a=1;
 connection default;
@@ -567,7 +567,7 @@ connection default;
 evalp show explain for $thr2;
 connection con1;
 reap;
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 
 DROP TABLE t1;
 
@@ -591,7 +591,7 @@ set join_cache_level=0;
 explain select count(*) from t1 A, t1 B where B.key1 < A.col2 and A.col1=3 AND B.col2 + 1 < 100;
 
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_test_if_quick_select';
+SET debug_dbug='+d,show_explain_probe_test_if_quick_select';
 
 send 
 select count(*) from t1 A, t1 B where B.key1 < A.col2 and A.col1=3 AND B.col2 + 1 < 100;
@@ -608,7 +608,7 @@ evalp show explain for $thr2;
 connection con1;
 reap;
 
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 drop table t1;
 
 --echo #
@@ -619,7 +619,7 @@ CREATE TABLE t1(a INT, b INT, c INT, KEY(a), KEY(b), KEY(c));
 INSERT INTO t1 (a) VALUES (3),(1),(5),(1);
 
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 
 send SHOW INDEX FROM t1;
 connection default;
@@ -627,7 +627,7 @@ connection default;
 evalp show explain for $thr2;
 connection con1;
 reap;
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 
 DROP TABLE t1;
 
@@ -641,7 +641,7 @@ CREATE ALGORITHM=TEMPTABLE VIEW v1 AS SELECT * FROM t1;
 
 EXPLAIN SELECT a + 1 FROM v1;
 
-set debug_dbug='+d,show_explain_probe_join_tab_preread';
+SET debug_dbug='+d,show_explain_probe_join_tab_preread';
 set @show_explain_probe_select_id=1;
 
 send
@@ -651,7 +651,7 @@ connection default;
 evalp show explain for $thr2;
 connection con1;
 reap;
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 
 DROP VIEW v1;
 DROP TABLE t1;
@@ -667,7 +667,7 @@ INSERT INTO t1 VALUES (4),(6);
 EXPLAIN 
 SELECT a FROM t1 WHERE a IN ( SELECT 1+SLEEP(0.01) UNION SELECT 2 );
 
-set debug_dbug='+d,show_explain_probe_union_read';
+SET debug_dbug='+d,show_explain_probe_union_read';
 send
 SELECT a FROM t1 WHERE a IN ( SELECT 1+SLEEP(0.01) UNION SELECT 2 );
 
@@ -681,7 +681,7 @@ evalp show explain for $thr2;
 connection con1;
 reap;
 
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 DROP TABLE t1;
 
 --echo #
@@ -703,7 +703,7 @@ SELECT * FROM t1, ( SELECT * FROM t2 ) AS alias
 WHERE a < ALL ( SELECT b FROM t1, t2 WHERE a = b );
 
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 --send
 SELECT * FROM t1, ( SELECT * FROM t2 ) AS alias
 WHERE a < ALL ( SELECT b FROM t1, t2 WHERE a = b );
@@ -714,7 +714,7 @@ evalp show explain for $thr2;
 
 connection con1;
 reap;
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 DROP TABLE t1, t2;
 
 --echo # 
@@ -737,7 +737,7 @@ insert into t3 select * from t4;
 explain select distinct t1.a from t1,t3 where t1.a=t3.a;
 
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 --send
 select distinct t1.a from t1,t3 where t1.a=t3.a;
 connection default;
@@ -746,7 +746,7 @@ evalp show explain for $thr2;
 
 connection con1;
 reap;
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 
 drop table t1,t3,t4;
 
@@ -756,7 +756,7 @@ drop table t1,t3,t4;
 create user test2@localhost;
 grant ALL on test.* to test2@localhost;
 
-# Give the user SUPER privilege so it can set debug_dbug variable.
+# Give the user SUPER privilege so it can SET debug_dbug variable.
 grant super on *.* to test2@localhost;
 connect (con2, localhost, test2,,);
 connection con1;
@@ -765,7 +765,7 @@ connection con1;
 --echo #  First, make sure that user 'test2' cannot do SHOW EXPLAIN on us
 --echo #
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 send
 select * from t0 where a < 3;
 
@@ -781,7 +781,7 @@ evalp show explain for $thr2;
 
 connection con1;
 reap;
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 
 --echo #
 --echo # Check that user test2 can do SHOW EXPLAIN on its own queries 
@@ -791,7 +791,7 @@ connect (con3, localhost, test2,,);
 connection con2;
 let $thr_con2=`select connection_id()`;
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 send
 select * from t0 where a < 3;
 
@@ -817,10 +817,10 @@ disconnect con2;
 grant process on *.* to test2@localhost;
 connect (con2, localhost, test2,,);
 connection con1;
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 send
 select * from t0 where a < 3;
 
@@ -832,7 +832,7 @@ evalp show explain for $thr2;
 
 connection con1;
 reap;
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 
 revoke all privileges on test.* from test2@localhost;
 drop user test2@localhost;
@@ -912,7 +912,7 @@ WHERE a IN ( 255, 0 ) OR b BETWEEN 6 AND 129
 ORDER BY b;
 
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 --send
 SELECT a+SLEEP(0.01) FROM t1
 WHERE a IN ( 255, 0 ) OR b BETWEEN 6 AND 129
@@ -924,10 +924,10 @@ evalp show explain for $thr2;
 
 connection con1;
 reap;
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_do_select';
+SET debug_dbug='+d,show_explain_probe_do_select';
 --send
 SELECT a+SLEEP(0.01) FROM t1
 WHERE a IN ( 255, 0 ) OR b BETWEEN 6 AND 129
@@ -940,7 +940,7 @@ evalp show explain for $thr2;
 connection con1;
 reap;
 
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 
 drop table t1;
 
@@ -956,7 +956,7 @@ INSERT INTO t1 SELECT t11.a FROM t1 t11, t1 t12, t1 t13;
 EXPLAIN SELECT a FROM t1 GROUP BY a;
 
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 --send
 SELECT a FROM t1 GROUP BY a;
 
@@ -967,7 +967,7 @@ evalp show explain for $thr2;
 connection con1;
 reap;
 
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 
 drop table t1;
 
@@ -983,7 +983,7 @@ INSERT INTO t2 VALUES (86,'English'),(87,'Russian');
 explain SELECT SUM(a + SLEEP(0.1)) FROM t1 WHERE a IN ( SELECT c FROM t2 WHERE d < b ) OR b < 's';
 
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 --send
 SELECT SUM(a + SLEEP(0.1)) FROM t1 WHERE a IN ( SELECT c FROM t2 WHERE d < b ) OR b < 's';
 
@@ -994,7 +994,7 @@ evalp show explain for $thr2;
 connection con1;
 reap;
 
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 drop table t1, t2;
 
 --echo #
@@ -1033,7 +1033,7 @@ explain
 SELECT b AS field1, b AS field2 FROM t1, t2, t3 WHERE d = b ORDER BY field1, field2;
 
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_do_select';
+SET debug_dbug='+d,show_explain_probe_do_select';
 
 send
 SELECT b AS field1, b AS field2 FROM t1, t2, t3 WHERE d = b ORDER BY field1, field2;
@@ -1045,7 +1045,7 @@ evalp show explain for $thr2;
 connection con1;
 reap;
 
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 
 DROP TABLE t1,t2,t3;
 
@@ -1069,7 +1069,7 @@ SELECT max(a+b+c) FROM t1 AS alias1, ( SELECT * FROM t2 ) AS alias
 WHERE EXISTS ( SELECT * FROM t3 WHERE b = c )  OR a <= 10;
 
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 
 send
 SELECT max(a+b+c) FROM t1 AS alias1, ( SELECT * FROM t2 ) AS alias 
@@ -1082,7 +1082,7 @@ evalp show explain for $thr2;
 connection con1;
 reap;
 
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 DROP TABLE t1,t2,t3;
 
 --echo #
@@ -1109,7 +1109,7 @@ select charset('��');
 select hex('��');
 
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 
 send
 select * from t0 where length('��') = a;
@@ -1124,7 +1124,7 @@ connection con1;
 # The constant should be two letters, the last looking like 'bl'
 reap;
 
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 set names default;
 
 --echo #
@@ -1151,7 +1151,7 @@ WHERE b <= ANY (
 
 
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_join_exec_start';
+SET debug_dbug='+d,show_explain_probe_join_exec_start';
 
 send
 SELECT SUM(b) FROM ( SELECT * FROM t1 ) AS alias1, t2 
@@ -1166,7 +1166,7 @@ evalp show explain for $thr2;
 connection con1;
 reap;
 
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 DROP TABLE t1,t2;
 drop table t0;
 
@@ -1182,7 +1182,7 @@ insert into t1 select a,a from t0;
 create table t2 as select * from t1;
 
 set @show_explain_probe_select_id=2;
-set debug_dbug='+d,show_explain_probe_best_ext_lim_search';
+SET debug_dbug='+d,show_explain_probe_best_ext_lim_search';
 send
 explain 
 select * from t0 
diff --git a/mysql-test/main/show_explain_non_select.result b/mysql-test/main/show_explain_non_select.result
index 6076a848e22..8d96056ca91 100644
--- a/mysql-test/main/show_explain_non_select.result
+++ b/mysql-test/main/show_explain_non_select.result
@@ -14,7 +14,7 @@ from t0 A, t0 B, t0 C;
 # Test SHOW EXPLAIN for single-table DELETE
 #
 connection con2;
-set debug_dbug='+d,show_explain_probe_delete_exec_start';
+SET debug_dbug='+d,show_explain_probe_delete_exec_start';
 delete from t1 where a<10 and b+1>1000;
 connection default;
 show explain for $thr2;
@@ -27,7 +27,7 @@ connection con2;
 # Test SHOW EXPLAIN for multi-table DELETE
 #
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_do_select';
+SET debug_dbug='+d,show_explain_probe_do_select';
 delete t1 from t1, t0 where t0.a=t1.a and t1.b +1 > 1000;
 connection default;
 show explain for $thr2;
@@ -41,7 +41,7 @@ connection con2;
 # Test SHOW EXPLAIN for single-table UPDATE
 #
 connection con2;
-set debug_dbug='+d,show_explain_probe_update_exec_start';
+SET debug_dbug='+d,show_explain_probe_update_exec_start';
 update t1 set filler='filler-data-2' where a<10 and b+1>1000;
 connection default;
 show explain for $thr2;
@@ -51,5 +51,5 @@ Warnings:
 Note	1003	update t1 set filler='filler-data-2' where a<10 and b+1>1000
 connection con2;
 drop table t0,t1;
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 set debug_sync='RESET';
diff --git a/mysql-test/main/show_explain_non_select.test b/mysql-test/main/show_explain_non_select.test
index 21b16739141..505e9296222 100644
--- a/mysql-test/main/show_explain_non_select.test
+++ b/mysql-test/main/show_explain_non_select.test
@@ -38,7 +38,7 @@ let $wait_condition= select State='show_explain_trap' from information_schema.pr
 --echo # Test SHOW EXPLAIN for single-table DELETE
 --echo #
 connection con2;
-set debug_dbug='+d,show_explain_probe_delete_exec_start';
+SET debug_dbug='+d,show_explain_probe_delete_exec_start';
 send delete from t1 where a<10 and b+1>1000;
 
 connection default;
@@ -51,7 +51,7 @@ reap;
 --echo # Test SHOW EXPLAIN for multi-table DELETE
 --echo #
 set @show_explain_probe_select_id=1;
-set debug_dbug='+d,show_explain_probe_do_select';
+SET debug_dbug='+d,show_explain_probe_do_select';
 send delete t1 from t1, t0 where t0.a=t1.a and t1.b +1 > 1000;
 connection default;
 --source include/wait_condition.inc
@@ -63,7 +63,7 @@ reap;
 --echo # Test SHOW EXPLAIN for single-table UPDATE
 --echo #
 connection con2;
-set debug_dbug='+d,show_explain_probe_update_exec_start';
+SET debug_dbug='+d,show_explain_probe_update_exec_start';
 send update t1 set filler='filler-data-2' where a<10 and b+1>1000;
 
 connection default;
@@ -74,5 +74,5 @@ reap;
 
 drop table t0,t1;
 
-set debug_dbug=@old_debug;
+SET debug_dbug=@old_debug;
 set debug_sync='RESET';
diff --git a/mysql-test/main/show_explain_ps.result b/mysql-test/main/show_explain_ps.result
index 69ee2cab31d..1c3be0d5953 100644
--- a/mysql-test/main/show_explain_ps.result
+++ b/mysql-test/main/show_explain_ps.result
@@ -17,7 +17,8 @@ connection con1;
 connection default;
 connection con1;
 set @show_explain_probe_select_id=1;
-set debug_dbug='d,show_explain_probe_join_exec_start';
+SET @saved_dbug = @@SESSION.debug_dbug;
+SET debug_dbug='d,show_explain_probe_join_exec_start';
 select count(*) from t0 where a < 100000;
 connection default;
 show explain for $thr2;
@@ -28,7 +29,7 @@ Note	1003	select count(*) from t0 where a < 100000
 connection con1;
 count(*)
 10
-set debug_dbug='';
+SET debug_dbug= @saved_dbug;
 select event_name
 from
 performance_schema.events_stages_history_long join
diff --git a/mysql-test/main/show_explain_ps.test b/mysql-test/main/show_explain_ps.test
index 13cd1538143..cbff0f50f96 100644
--- a/mysql-test/main/show_explain_ps.test
+++ b/mysql-test/main/show_explain_ps.test
@@ -38,7 +38,8 @@ let $wait_condition= select State='show_explain_trap' from information_schema.pr
 #
 connection con1;
 set @show_explain_probe_select_id=1;
-set debug_dbug='d,show_explain_probe_join_exec_start';
+SET @saved_dbug = @@SESSION.debug_dbug;
+SET debug_dbug='d,show_explain_probe_join_exec_start';
 send select count(*) from t0 where a < 100000;
 
 connection default;
@@ -47,7 +48,7 @@ evalp show explain for $thr2;
 connection con1;
 reap;
 
-set debug_dbug='';
+SET debug_dbug= @saved_dbug;
 
 evalp select event_name
         from
diff --git a/mysql-test/main/slowlog_enospace-10508.result b/mysql-test/main/slowlog_enospace-10508.result
index f39bfa2f00e..66fb19eed6a 100644
--- a/mysql-test/main/slowlog_enospace-10508.result
+++ b/mysql-test/main/slowlog_enospace-10508.result
@@ -3,7 +3,8 @@ create table t1 (a int, b int) engine=memory;
 insert t1 select seq, seq+1 from seq_1_to_1000;
 set global general_log=0;
 set global log_queries_not_using_indexes=1;
-set debug_dbug='+d,simulate_file_write_error';
+SET @saved_dbug = @@SESSION.debug_dbug;
+SET debug_dbug='+d,simulate_file_write_error';
 select * from t1 where a>10;
 select * from t1 where a>10;
 select * from t1 where a>10;
@@ -54,7 +55,7 @@ select * from t1 where a>10;
 select * from t1 where a>10;
 select * from t1 where a>10;
 select * from t1 where a>10;
-set debug_dbug='';
+SET debug_dbug= @saved_dbug;
 set global general_log=1;
 set global log_queries_not_using_indexes=default;
 drop table t1;
diff --git a/mysql-test/main/slowlog_enospace-10508.test b/mysql-test/main/slowlog_enospace-10508.test
index b2c26a5984d..74dca21f8ec 100644
--- a/mysql-test/main/slowlog_enospace-10508.test
+++ b/mysql-test/main/slowlog_enospace-10508.test
@@ -9,7 +9,8 @@ create table t1 (a int, b int) engine=memory;
 insert t1 select seq, seq+1 from seq_1_to_1000;
 set global general_log=0;
 set global log_queries_not_using_indexes=1;
-set debug_dbug='+d,simulate_file_write_error';
+SET @saved_dbug = @@SESSION.debug_dbug;
+SET debug_dbug='+d,simulate_file_write_error';
 --disable_result_log
 --let $run= 50
 while ($run)
@@ -18,7 +19,7 @@ while ($run)
     dec $run;
 }
 --enable_result_log
-set debug_dbug='';
+SET debug_dbug= @saved_dbug;
 set global general_log=1;
 set global log_queries_not_using_indexes=default;
 drop table t1;
diff --git a/mysql-test/main/stat_tables-enospc.result b/mysql-test/main/stat_tables-enospc.result
index 943cbca6bc5..9ac24a2af99 100644
--- a/mysql-test/main/stat_tables-enospc.result
+++ b/mysql-test/main/stat_tables-enospc.result
@@ -1,11 +1,12 @@
 call mtr.add_suppression("No space left on device");
 create table t1 (a varchar(255), b varchar(255), c varchar(255));
 set use_stat_tables=PREFERABLY, optimizer_use_condition_selectivity=3;
-set debug_dbug='+d,simulate_file_write_error';
+SET @saved_dbug = @@SESSION.debug_dbug;
+SET debug_dbug='+d,simulate_file_write_error';
 set @@max_heap_table_size=128*1024;
 analyze table t1;
 Table	Op	Msg_type	Msg_text
 test.t1	analyze	Error	Error writing file 'tmp-file' (Errcode: 28 "No space left on device")
 test.t1	analyze	status	Operation failed
-set debug_dbug='';
+SET debug_dbug= @saved_dbug;
 drop table t1;
diff --git a/mysql-test/main/stat_tables-enospc.test b/mysql-test/main/stat_tables-enospc.test
index 932b2bde302..fe8fe3590ae 100644
--- a/mysql-test/main/stat_tables-enospc.test
+++ b/mysql-test/main/stat_tables-enospc.test
@@ -16,9 +16,10 @@ while ($i) {
 }
 --enable_query_log
 set use_stat_tables=PREFERABLY, optimizer_use_condition_selectivity=3;
-set debug_dbug='+d,simulate_file_write_error';
+SET @saved_dbug = @@SESSION.debug_dbug;
+SET debug_dbug='+d,simulate_file_write_error';
 set @@max_heap_table_size=128*1024;
 --replace_regex /'.*'/'tmp-file'/
 analyze table t1;
-set debug_dbug='';
+SET debug_dbug= @saved_dbug;
 drop table t1;
diff --git a/mysql-test/main/union_crash-714.result b/mysql-test/main/union_crash-714.result
index 4a51f88b76f..371be1e03d0 100644
--- a/mysql-test/main/union_crash-714.result
+++ b/mysql-test/main/union_crash-714.result
@@ -1,5 +1,7 @@
 create table t1 (i tinyint);
-set debug_dbug='+d,bug11747970_raise_error';
+SET @saved_dbug = @@SESSION.debug_dbug;
+SET debug_dbug='+d,bug11747970_raise_error';
 insert into t1 (i) select i from t1 union select i from t1;
 ERROR 70100: Query execution was interrupted
 drop table t1;
+SET debug_dbug= @saved_dbug;
diff --git a/mysql-test/main/union_crash-714.test b/mysql-test/main/union_crash-714.test
index 6c31a2202cb..90b849037f2 100644
--- a/mysql-test/main/union_crash-714.test
+++ b/mysql-test/main/union_crash-714.test
@@ -3,7 +3,9 @@
 #
 --source include/have_debug.inc
 create table t1 (i tinyint);
-set debug_dbug='+d,bug11747970_raise_error';
+SET @saved_dbug = @@SESSION.debug_dbug;
+SET debug_dbug='+d,bug11747970_raise_error';
 --error ER_QUERY_INTERRUPTED
 insert into t1 (i) select i from t1 union select i from t1;
 drop table t1;
+SET debug_dbug= @saved_dbug;
+\ No newline at end of file
diff --git a/mysql-test/main/warnings_debug.result b/mysql-test/main/warnings_debug.result
index 4cdce7a5feb..3a9d8225795 100644
--- a/mysql-test/main/warnings_debug.result
+++ b/mysql-test/main/warnings_debug.result
@@ -1,5 +1,6 @@
 drop table if exists t1;
 create table t1 (a int primary key) engine=innodb;
+SET @saved_dbug = @@SESSION.debug_dbug;
 SET SESSION debug_dbug="+d,warn_during_ha_commit_trans";
 INSERT INTO t1 VALUES (1);
 Warnings:
@@ -8,3 +9,4 @@ SHOW WARNINGS;
 Level	Code	Message
 Warning	1196	Some non-transactional changed tables couldn't be rolled back
 drop table t1;
+SET debug_dbug= @saved_dbug;
diff --git a/mysql-test/main/warnings_debug.test b/mysql-test/main/warnings_debug.test
index 3055e3894e5..6605daf875d 100644
--- a/mysql-test/main/warnings_debug.test
+++ b/mysql-test/main/warnings_debug.test
@@ -9,6 +9,7 @@ create table t1 (a int primary key) engine=innodb;
 
 # Test that warnings produced during autocommit (after calling
 # set_ok_status()) are still reported to the client.
+SET @saved_dbug = @@SESSION.debug_dbug;
 SET SESSION debug_dbug="+d,warn_during_ha_commit_trans";
 INSERT INTO t1 VALUES (1);
 # The warning will be shown automatically by mysqltest; there was a bug where
@@ -17,3 +18,4 @@ INSERT INTO t1 VALUES (1);
 SHOW WARNINGS;
 
 drop table t1;
+SET debug_dbug= @saved_dbug;
diff --git a/mysql-test/suite/binlog/include/binlog_ioerr.inc b/mysql-test/suite/binlog/include/binlog_ioerr.inc
index 8d1069bacb0..da6fb5ac727 100644
--- a/mysql-test/suite/binlog/include/binlog_ioerr.inc
+++ b/mysql-test/suite/binlog/include/binlog_ioerr.inc
@@ -15,12 +15,13 @@ RESET MASTER;
 
 CREATE TABLE t1 (a INT PRIMARY KEY) ENGINE=innodb;
 INSERT INTO t1 VALUES(0);
+SET @saved_dbug = @@SESSION.debug_dbug;
 SET SESSION debug_dbug='+d,fail_binlog_write_1';
 --error ER_ERROR_ON_WRITE
 INSERT INTO t1 VALUES(1);
 --error ER_ERROR_ON_WRITE
 INSERT INTO t1 VALUES(2);
-SET SESSION debug_dbug='';
+SET SESSION debug_dbug=@saved_dbug;
 INSERT INTO t1 VALUES(3);
 SELECT * FROM t1;
 
diff --git a/mysql-test/suite/binlog/r/binlog_ioerr.result b/mysql-test/suite/binlog/r/binlog_ioerr.result
index 1d3c3d7d12d..e4f00a017ba 100644
--- a/mysql-test/suite/binlog/r/binlog_ioerr.result
+++ b/mysql-test/suite/binlog/r/binlog_ioerr.result
@@ -2,12 +2,13 @@ CALL mtr.add_suppression("Error writing file 'master-bin'");
 RESET MASTER;
 CREATE TABLE t1 (a INT PRIMARY KEY) ENGINE=innodb;
 INSERT INTO t1 VALUES(0);
+SET @saved_dbug = @@SESSION.debug_dbug;
 SET SESSION debug_dbug='+d,fail_binlog_write_1';
 INSERT INTO t1 VALUES(1);
 ERROR HY000: Error writing file 'master-bin' (errno: 28 "No space left on device")
 INSERT INTO t1 VALUES(2);
 ERROR HY000: Error writing file 'master-bin' (errno: 28 "No space left on device")
-SET SESSION debug_dbug='';
+SET SESSION debug_dbug=@saved_dbug;
 INSERT INTO t1 VALUES(3);
 SELECT * FROM t1;
 a
diff --git a/mysql-test/suite/binlog/r/binlog_write_error.result b/mysql-test/suite/binlog/r/binlog_write_error.result
index 2606a9f40b3..6e8a212035a 100644
--- a/mysql-test/suite/binlog/r/binlog_write_error.result
+++ b/mysql-test/suite/binlog/r/binlog_write_error.result
@@ -12,92 +12,109 @@ DROP VIEW IF EXISTS v1, v2;
 #
 # Test injecting binlog write error when executing queries
 #
+set @saved_dbug = @@global.debug_dbug;
 SET GLOBAL debug_dbug='d,injecting_fault_writing';
 CREATE TABLE t1 (a INT);
 CREATE TABLE t1 (a INT);
 ERROR HY000: Error writing file 'master-bin' ((errno: #)
-SET GLOBAL debug_dbug='';
+set @@global.debug_dbug = @saved_dbug;
 INSERT INTO t1 VALUES (1),(2),(3);
+set @saved_dbug = @@global.debug_dbug;
 SET GLOBAL debug_dbug='d,injecting_fault_writing';
 INSERT INTO t1 VALUES (4),(5),(6);
 INSERT INTO t1 VALUES (4),(5),(6);
 ERROR HY000: Error writing file 'master-bin' ((errno: #)
-SET GLOBAL debug_dbug='';
+set @@global.debug_dbug = @saved_dbug;
+set @saved_dbug = @@global.debug_dbug;
 SET GLOBAL debug_dbug='d,injecting_fault_writing';
 UPDATE t1 set a=a+1;
 UPDATE t1 set a=a+1;
 ERROR HY000: Error writing file 'master-bin' ((errno: #)
-SET GLOBAL debug_dbug='';
+set @@global.debug_dbug = @saved_dbug;
+set @saved_dbug = @@global.debug_dbug;
 SET GLOBAL debug_dbug='d,injecting_fault_writing';
 DELETE FROM t1;
 DELETE FROM t1;
 ERROR HY000: Error writing file 'master-bin' ((errno: #)
-SET GLOBAL debug_dbug='';
+set @@global.debug_dbug = @saved_dbug;
+set @saved_dbug = @@global.debug_dbug;
 SET GLOBAL debug_dbug='d,injecting_fault_writing';
 CREATE TRIGGER tr1 AFTER INSERT ON t1 FOR EACH ROW INSERT INTO t1 VALUES (new.a + 100);
 CREATE TRIGGER tr1 AFTER INSERT ON t1 FOR EACH ROW INSERT INTO t1 VALUES (new.a + 100);
 ERROR HY000: Error writing file 'master-bin' ((errno: #)
-SET GLOBAL debug_dbug='';
+set @@global.debug_dbug = @saved_dbug;
+set @saved_dbug = @@global.debug_dbug;
 SET GLOBAL debug_dbug='d,injecting_fault_writing';
 DROP TRIGGER tr1;
 DROP TRIGGER tr1;
 ERROR HY000: Error writing file 'master-bin' ((errno: #)
-SET GLOBAL debug_dbug='';
+set @@global.debug_dbug = @saved_dbug;
+set @saved_dbug = @@global.debug_dbug;
 SET GLOBAL debug_dbug='d,injecting_fault_writing';
 ALTER TABLE t1 ADD (b INT);
 ALTER TABLE t1 ADD (b INT);
 ERROR HY000: Error writing file 'master-bin' ((errno: #)
-SET GLOBAL debug_dbug='';
+set @@global.debug_dbug = @saved_dbug;
+set @saved_dbug = @@global.debug_dbug;
 SET GLOBAL debug_dbug='d,injecting_fault_writing';
 CREATE VIEW v1 AS SELECT a FROM t1;
 CREATE VIEW v1 AS SELECT a FROM t1;
 ERROR HY000: Error writing file 'master-bin' ((errno: #)
-SET GLOBAL debug_dbug='';
+set @@global.debug_dbug = @saved_dbug;
+set @saved_dbug = @@global.debug_dbug;
 SET GLOBAL debug_dbug='d,injecting_fault_writing';
 DROP VIEW v1;
 DROP VIEW v1;
 ERROR HY000: Error writing file 'master-bin' ((errno: #)
-SET GLOBAL debug_dbug='';
+set @@global.debug_dbug = @saved_dbug;
+set @saved_dbug = @@global.debug_dbug;
 SET GLOBAL debug_dbug='d,injecting_fault_writing';
 CREATE PROCEDURE p1(OUT rows_cnt INT) SELECT count(*) INTO rows_cnt FROM t1;
 CREATE PROCEDURE p1(OUT rows_cnt INT) SELECT count(*) INTO rows_cnt FROM t1;
 ERROR HY000: Error writing file 'master-bin' ((errno: #)
-SET GLOBAL debug_dbug='';
+set @@global.debug_dbug = @saved_dbug;
+set @saved_dbug = @@global.debug_dbug;
 SET GLOBAL debug_dbug='d,injecting_fault_writing';
 DROP PROCEDURE p1;
 DROP PROCEDURE p1;
 ERROR HY000: Error writing file 'master-bin' ((errno: #)
-SET GLOBAL debug_dbug='';
+set @@global.debug_dbug = @saved_dbug;
+set @saved_dbug = @@global.debug_dbug;
 SET GLOBAL debug_dbug='d,injecting_fault_writing';
 DROP TABLE t1;
 DROP TABLE t1;
 ERROR HY000: Error writing file 'master-bin' ((errno: #)
-SET GLOBAL debug_dbug='';
+set @@global.debug_dbug = @saved_dbug;
+set @saved_dbug = @@global.debug_dbug;
 SET GLOBAL debug_dbug='d,injecting_fault_writing';
 CREATE FUNCTION f1() RETURNS INT return 1;
 CREATE FUNCTION f1() RETURNS INT return 1;
 ERROR HY000: Error writing file 'master-bin' ((errno: #)
-SET GLOBAL debug_dbug='';
+set @@global.debug_dbug = @saved_dbug;
+set @saved_dbug = @@global.debug_dbug;
 SET GLOBAL debug_dbug='d,injecting_fault_writing';
 DROP FUNCTION f1;
 DROP FUNCTION f1;
 ERROR HY000: Error writing file 'master-bin' ((errno: #)
-SET GLOBAL debug_dbug='';
+set @@global.debug_dbug = @saved_dbug;
+set @saved_dbug = @@global.debug_dbug;
 SET GLOBAL debug_dbug='d,injecting_fault_writing';
 CREATE USER user1;
 CREATE USER user1;
 ERROR HY000: Error writing file 'master-bin' ((errno: #)
-SET GLOBAL debug_dbug='';
+set @@global.debug_dbug = @saved_dbug;
+set @saved_dbug = @@global.debug_dbug;
 SET GLOBAL debug_dbug='d,injecting_fault_writing';
 REVOKE ALL PRIVILEGES, GRANT OPTION FROM user1;
 REVOKE ALL PRIVILEGES, GRANT OPTION FROM user1;
 ERROR HY000: Error writing file 'master-bin' ((errno: #)
-SET GLOBAL debug_dbug='';
+set @@global.debug_dbug = @saved_dbug;
+set @saved_dbug = @@global.debug_dbug;
 SET GLOBAL debug_dbug='d,injecting_fault_writing';
 DROP USER user1;
 DROP USER user1;
 ERROR HY000: Error writing file 'master-bin' ((errno: #)
-SET GLOBAL debug_dbug='';
+set @@global.debug_dbug = @saved_dbug;
 #
 # Cleanup
 #
diff --git a/mysql-test/suite/binlog_encryption/binlog_ioerr.result b/mysql-test/suite/binlog_encryption/binlog_ioerr.result
index 6b3120b6d89..2823b7050c3 100644
--- a/mysql-test/suite/binlog_encryption/binlog_ioerr.result
+++ b/mysql-test/suite/binlog_encryption/binlog_ioerr.result
@@ -2,12 +2,13 @@ CALL mtr.add_suppression("Error writing file 'master-bin'");
 RESET MASTER;
 CREATE TABLE t1 (a INT PRIMARY KEY) ENGINE=innodb;
 INSERT INTO t1 VALUES(0);
+SET @saved_dbug = @@SESSION.debug_dbug;
 SET SESSION debug_dbug='+d,fail_binlog_write_1';
 INSERT INTO t1 VALUES(1);
 ERROR HY000: Error writing file 'master-bin' (errno: 28 "No space left on device")
 INSERT INTO t1 VALUES(2);
 ERROR HY000: Error writing file 'master-bin' (errno: 28 "No space left on device")
-SET SESSION debug_dbug='';
+SET SESSION debug_dbug=@saved_dbug;
 INSERT INTO t1 VALUES(3);
 SELECT * FROM t1;
 a
diff --git a/mysql-test/suite/binlog_encryption/binlog_write_error.result b/mysql-test/suite/binlog_encryption/binlog_write_error.result
index 2606a9f40b3..6e8a212035a 100644
--- a/mysql-test/suite/binlog_encryption/binlog_write_error.result
+++ b/mysql-test/suite/binlog_encryption/binlog_write_error.result
@@ -12,92 +12,109 @@ DROP VIEW IF EXISTS v1, v2;
 #
 # Test injecting binlog write error when executing queries
 #
+set @saved_dbug = @@global.debug_dbug;
 SET GLOBAL debug_dbug='d,injecting_fault_writing';
 CREATE TABLE t1 (a INT);
 CREATE TABLE t1 (a INT);
 ERROR HY000: Error writing file 'master-bin' ((errno: #)
-SET GLOBAL debug_dbug='';
+set @@global.debug_dbug = @saved_dbug;
 INSERT INTO t1 VALUES (1),(2),(3);
+set @saved_dbug = @@global.debug_dbug;
 SET GLOBAL debug_dbug='d,injecting_fault_writing';
 INSERT INTO t1 VALUES (4),(5),(6);
 INSERT INTO t1 VALUES (4),(5),(6);
 ERROR HY000: Error writing file 'master-bin' ((errno: #)
-SET GLOBAL debug_dbug='';
+set @@global.debug_dbug = @saved_dbug;
+set @saved_dbug = @@global.debug_dbug;
 SET GLOBAL debug_dbug='d,injecting_fault_writing';
 UPDATE t1 set a=a+1;
 UPDATE t1 set a=a+1;
 ERROR HY000: Error writing file 'master-bin' ((errno: #)
-SET GLOBAL debug_dbug='';
+set @@global.debug_dbug = @saved_dbug;
+set @saved_dbug = @@global.debug_dbug;
 SET GLOBAL debug_dbug='d,injecting_fault_writing';
 DELETE FROM t1;
 DELETE FROM t1;
 ERROR HY000: Error writing file 'master-bin' ((errno: #)
-SET GLOBAL debug_dbug='';
+set @@global.debug_dbug = @saved_dbug;
+set @saved_dbug = @@global.debug_dbug;
 SET GLOBAL debug_dbug='d,injecting_fault_writing';
 CREATE TRIGGER tr1 AFTER INSERT ON t1 FOR EACH ROW INSERT INTO t1 VALUES (new.a + 100);
 CREATE TRIGGER tr1 AFTER INSERT ON t1 FOR EACH ROW INSERT INTO t1 VALUES (new.a + 100);
 ERROR HY000: Error writing file 'master-bin' ((errno: #)
-SET GLOBAL debug_dbug='';
+set @@global.debug_dbug = @saved_dbug;
+set @saved_dbug = @@global.debug_dbug;
 SET GLOBAL debug_dbug='d,injecting_fault_writing';
 DROP TRIGGER tr1;
 DROP TRIGGER tr1;
 ERROR HY000: Error writing file 'master-bin' ((errno: #)
-SET GLOBAL debug_dbug='';
+set @@global.debug_dbug = @saved_dbug;
+set @saved_dbug = @@global.debug_dbug;
 SET GLOBAL debug_dbug='d,injecting_fault_writing';
 ALTER TABLE t1 ADD (b INT);
 ALTER TABLE t1 ADD (b INT);
 ERROR HY000: Error writing file 'master-bin' ((errno: #)
-SET GLOBAL debug_dbug='';
+set @@global.debug_dbug = @saved_dbug;
+set @saved_dbug = @@global.debug_dbug;
 SET GLOBAL debug_dbug='d,injecting_fault_writing';
 CREATE VIEW v1 AS SELECT a FROM t1;
 CREATE VIEW v1 AS SELECT a FROM t1;
 ERROR HY000: Error writing file 'master-bin' ((errno: #)
-SET GLOBAL debug_dbug='';
+set @@global.debug_dbug = @saved_dbug;
+set @saved_dbug = @@global.debug_dbug;
 SET GLOBAL debug_dbug='d,injecting_fault_writing';
 DROP VIEW v1;
 DROP VIEW v1;
 ERROR HY000: Error writing file 'master-bin' ((errno: #)
-SET GLOBAL debug_dbug='';
+set @@global.debug_dbug = @saved_dbug;
+set @saved_dbug = @@global.debug_dbug;
 SET GLOBAL debug_dbug='d,injecting_fault_writing';
 CREATE PROCEDURE p1(OUT rows_cnt INT) SELECT count(*) INTO rows_cnt FROM t1;
 CREATE PROCEDURE p1(OUT rows_cnt INT) SELECT count(*) INTO rows_cnt FROM t1;
 ERROR HY000: Error writing file 'master-bin' ((errno: #)
-SET GLOBAL debug_dbug='';
+set @@global.debug_dbug = @saved_dbug;
+set @saved_dbug = @@global.debug_dbug;
 SET GLOBAL debug_dbug='d,injecting_fault_writing';
 DROP PROCEDURE p1;
 DROP PROCEDURE p1;
 ERROR HY000: Error writing file 'master-bin' ((errno: #)
-SET GLOBAL debug_dbug='';
+set @@global.debug_dbug = @saved_dbug;
+set @saved_dbug = @@global.debug_dbug;
 SET GLOBAL debug_dbug='d,injecting_fault_writing';
 DROP TABLE t1;
 DROP TABLE t1;
 ERROR HY000: Error writing file 'master-bin' ((errno: #)
-SET GLOBAL debug_dbug='';
+set @@global.debug_dbug = @saved_dbug;
+set @saved_dbug = @@global.debug_dbug;
 SET GLOBAL debug_dbug='d,injecting_fault_writing';
 CREATE FUNCTION f1() RETURNS INT return 1;
 CREATE FUNCTION f1() RETURNS INT return 1;
 ERROR HY000: Error writing file 'master-bin' ((errno: #)
-SET GLOBAL debug_dbug='';
+set @@global.debug_dbug = @saved_dbug;
+set @saved_dbug = @@global.debug_dbug;
 SET GLOBAL debug_dbug='d,injecting_fault_writing';
 DROP FUNCTION f1;
 DROP FUNCTION f1;
 ERROR HY000: Error writing file 'master-bin' ((errno: #)
-SET GLOBAL debug_dbug='';
+set @@global.debug_dbug = @saved_dbug;
+set @saved_dbug = @@global.debug_dbug;
 SET GLOBAL debug_dbug='d,injecting_fault_writing';
 CREATE USER user1;
 CREATE USER user1;
 ERROR HY000: Error writing file 'master-bin' ((errno: #)
-SET GLOBAL debug_dbug='';
+set @@global.debug_dbug = @saved_dbug;
+set @saved_dbug = @@global.debug_dbug;
 SET GLOBAL debug_dbug='d,injecting_fault_writing';
 REVOKE ALL PRIVILEGES, GRANT OPTION FROM user1;
 REVOKE ALL PRIVILEGES, GRANT OPTION FROM user1;
 ERROR HY000: Error writing file 'master-bin' ((errno: #)
-SET GLOBAL debug_dbug='';
+set @@global.debug_dbug = @saved_dbug;
+set @saved_dbug = @@global.debug_dbug;
 SET GLOBAL debug_dbug='d,injecting_fault_writing';
 DROP USER user1;
 DROP USER user1;
 ERROR HY000: Error writing file 'master-bin' ((errno: #)
-SET GLOBAL debug_dbug='';
+set @@global.debug_dbug = @saved_dbug;
 #
 # Cleanup
 #
diff --git a/mysql-test/suite/binlog_encryption/rpl_checksum.result b/mysql-test/suite/binlog_encryption/rpl_checksum.result
index 41c4cd94aff..22220b8e9fb 100644
--- a/mysql-test/suite/binlog_encryption/rpl_checksum.result
+++ b/mysql-test/suite/binlog_encryption/rpl_checksum.result
@@ -76,6 +76,7 @@ connection master;
 set @@global.binlog_checksum = CRC32;
 insert into t1 values (1) /* will not be applied on slave due to simulation */;
 connection slave;
+set @saved_dbug = @@global.debug_dbug;
 set @@global.debug_dbug='d,simulate_slave_unaware_checksum';
 start slave;
 include/wait_for_slave_io_error.inc [errno=1236]
@@ -83,15 +84,16 @@ Last_IO_Error = 'Got fatal error 1236 from master when reading data from binary
 select count(*) as zero from t1;
 zero
 0
-set @@global.debug_dbug='';
+set @@global.debug_dbug = @saved_dbug;
 connection slave;
 include/start_slave.inc
 connection master;
 set @@global.master_verify_checksum = 1;
+set @save_dbug = @@session.debug_dbug;
 set @@session.debug_dbug='d,simulate_checksum_test_failure';
 show binlog events;
 ERROR HY000: Error when executing command SHOW BINLOG EVENTS: Wrong offset or I/O error
-set @@session.debug_dbug='';
+SET debug_dbug= @save_dbug;
 set @@global.master_verify_checksum = default;
 connection slave;
 connection slave;
@@ -99,10 +101,11 @@ include/stop_slave.inc
 connection master;
 create table t2 (a int);
 connection slave;
+set @saved_dbug = @@global.debug_dbug;
 set @@global.debug_dbug='d,simulate_checksum_test_failure';
 start slave io_thread;
 include/wait_for_slave_io_error.inc [errno=1595,1913]
-set @@global.debug_dbug='';
+set @@global.debug_dbug = @saved_dbug;
 start slave io_thread;
 include/wait_for_slave_param.inc [Read_Master_Log_Pos]
 set @@global.slave_sql_verify_checksum = 1;
@@ -110,7 +113,7 @@ set @@global.debug_dbug='d,simulate_checksum_test_failure';
 start slave sql_thread;
 include/wait_for_slave_sql_error.inc [errno=1593]
 Last_SQL_Error = 'Error initializing relay log position: I/O error reading event at position 4'
-set @@global.debug_dbug='';
+set @@global.debug_dbug = @saved_dbug;
 include/start_slave.inc
 connection master;
 connection slave;
diff --git a/mysql-test/suite/binlog_encryption/rpl_corruption.result b/mysql-test/suite/binlog_encryption/rpl_corruption.result
index 25a82fd60cd..db72bb304fc 100644
--- a/mysql-test/suite/binlog_encryption/rpl_corruption.result
+++ b/mysql-test/suite/binlog_encryption/rpl_corruption.result
@@ -13,6 +13,7 @@ connection master;
 CREATE TABLE t1 (a INT NOT NULL PRIMARY KEY, b VARCHAR(10), c VARCHAR(100));
 include/stop_slave.inc
 # 2. Corruption in master binlog and SHOW BINLOG EVENTS
+set @saved_dbug = @@global.debug_dbug;
 SET GLOBAL debug_dbug="+d,corrupt_read_log_event_char";
 SHOW BINLOG EVENTS;
 ERROR HY000: Error when executing command SHOW BINLOG EVENTS: Wrong offset or I/O error
@@ -55,9 +56,9 @@ connection slave;
 include/diff_tables.inc [master:test.t1, slave:test.t1]
 # 8. Clean up
 connection master;
-SET GLOBAL debug_dbug= "";
+set @@global.debug_dbug = @saved_dbug;
 SET GLOBAL master_verify_checksum = @old_master_verify_checksum;
 DROP TABLE t1;
 connection slave;
-SET GLOBAL debug_dbug= "";
+set @@global.debug_dbug = @saved_dbug;
 include/rpl_end.inc
diff --git a/mysql-test/suite/binlog_encryption/rpl_incident.result b/mysql-test/suite/binlog_encryption/rpl_incident.result
index 8fb4aa907cc..6dbe4417c5a 100644
--- a/mysql-test/suite/binlog_encryption/rpl_incident.result
+++ b/mysql-test/suite/binlog_encryption/rpl_incident.result
@@ -14,6 +14,7 @@ a
 1
 2
 3
+set @saved_dbug = @@global.debug_dbug;
 SET GLOBAL debug_dbug= '+d,incident_database_resync_on_replace,*';
 REPLACE INTO t1 VALUES (4);
 SELECT * FROM t1;
@@ -22,6 +23,7 @@ a
 2
 3
 4
+set @@global.debug_dbug = @saved_dbug;
 connection slave;
 call mtr.add_suppression("Slave SQL.*The incident LOST_EVENTS occurred on the master.* 1590");
 include/wait_for_slave_sql_error.inc [errno=1590]
diff --git a/mysql-test/suite/binlog_encryption/rpl_init_slave_errors.result b/mysql-test/suite/binlog_encryption/rpl_init_slave_errors.result
index 91742814b4c..fc23734c645 100644
--- a/mysql-test/suite/binlog_encryption/rpl_init_slave_errors.result
+++ b/mysql-test/suite/binlog_encryption/rpl_init_slave_errors.result
@@ -4,12 +4,13 @@ connection slave;
 stop slave;
 reset slave;
 connection slave;
+set @saved_dbug = @@global.debug_dbug;
 SET GLOBAL debug_dbug= "d,simulate_io_slave_error_on_init,simulate_sql_slave_error_on_init";
 start slave;
 include/wait_for_slave_sql_error.inc [errno=1593]
 Last_SQL_Error = 'Failed during slave thread initialization'
 call mtr.add_suppression("Failed during slave.* thread initialization");
-SET GLOBAL debug_dbug= "";
+set @@global.debug_dbug = @saved_dbug;
 connection slave;
 reset slave;
 SET GLOBAL init_slave= "garbage";
diff --git a/mysql-test/suite/galera/disabled.def b/mysql-test/suite/galera/disabled.def
index c3db249ede3..202c9b6d82b 100644
--- a/mysql-test/suite/galera/disabled.def
+++ b/mysql-test/suite/galera/disabled.def
@@ -11,23 +11,38 @@
 ##############################################################################
 
 MW-286 : MDEV-18464 Killing thread can cause mutex deadlock if done concurrently with Galera/replication victim kill
+MW-328A : MDEV-21483 galera.MW-328A galera.MW-328B
+MW-328B : MDEV-21483 galera.MW-328A galera.MW-328B
 MW-329 : MDEV-19962 Galera test failure on MW-329
-MW-388: MDEV-19803 Long semaphore wait error on galera.MW-388	
+MW-336 : MDEV-17062 Test failure on galera.MW-336
+galera.galera_defaults : MDEV-21494 Galera test sporadic failure on galera.galera_defaults
 galera_account_management : MariaDB 10.0 does not support ALTER USER
 galera_as_master_gtid : Requires MySQL GTID
 galera_as_master_gtid_change_master : Requires MySQL GTID
+galera_as_slave_gtid_myisam : MDEV-21421 galera.galera_as_slave_gtid_myisam
 galera_as_slave_preordered : wsrep-preordered feature not merged to MariaDB
 galera_as_slave_replication_bundle : MDEV-15785 OPTION_GTID_BEGIN is set in Gtid_log_event::do_apply_event()
 galera_autoinc_sst_mariabackup : Known issue, may require porting MDEV-17458 from later versions
 galera_binlog_rows_query_log_events: MariaDB does not support binlog_rows_query_log_events
+galera_binlog_stmt_autoinc : MDEV-19959 Galera test failure on galera_binlog_stmt_autoinc	
 galera_binlog_stmt_autoinc: MDEV-19959 Galera test failure on galera_binlog_stmt_autoinc
 galera_flush :  MariaDB does not have global.thread_statistics
 galera_gcache_recover_manytrx : MDEV-18834 Galera test failure
 galera_ist_mariabackup : MDEV-18829 test leaves port open
 galera_ist_progress : MDEV-15236 fails when trying to read transfer status
+galera_load_data : MDEV-19968 galera.galera_load_data
 galera_migrate : MariaDB does not support START SLAVE USER
+galera_parallel_autoinc_largetrx : MDEV-20916 galera.galera_parallel_autoinc_largetrx
+galera_parallel_simple : MDEV-20318 galera.galera_parallel_simple fails	
+galera_shutdown_nonprim : MDEV-21493 galera.galera_shutdown_nonprim
 galera_ssl_upgrade : MDEV-19950 Galera test failure on galera_ssl_upgrade
+galera_sst_mariabackup_encrypt_with_key : MDEV-21484 galera_sst_mariabackup_encrypt_with_key
+galera_sst_mariabackup_table_options: MDEV-19741 Galera test failure on galera.galera_sst_mariabackup_table_options	 
+galera_var_innodb_disallow_writes : MDEV-20928 galera.galera_var_innodb_disallow_writes
 galera_var_node_address : MDEV-20485 Galera test failure
+galera_var_notify_cmd : MDEV-21488 galera.galera_var_notify_cmd
 galera_wan : MDEV-17259 Test failure on galera.galera_wan
+mysql-wsrep#33 : MDEV-21420 galera.mysql-wsrep#33
 partition : MDEV-19958 Galera test failure on galera.partition
 query_cache: MDEV-15805 Test failure on galera.query_cache
+sql_log_bin : MDEV-21491 galera.sql_log_bin
diff --git a/mysql-test/suite/galera/r/MW-388.result b/mysql-test/suite/galera/r/MW-388.result
index a2cf02712bb..59d499e117d 100644
--- a/mysql-test/suite/galera/r/MW-388.result
+++ b/mysql-test/suite/galera/r/MW-388.result
@@ -18,12 +18,10 @@ connection node_1a;
 SET SESSION DEBUG_SYNC = "now WAIT_FOR sync.wsrep_apply_cb_reached";
 connection node_1;
 SET SESSION wsrep_sync_wait = 0;
-SET SESSION DEBUG_SYNC = 'wsrep_after_replication SIGNAL wsrep_after_replication_reached WAIT_FOR wsrep_after_replication_continue';
 CALL insert_proc ();;
 connection node_1a;
-SET SESSION DEBUG_SYNC = "now WAIT_FOR wsrep_after_replication_reached";
+SET SESSION wsrep_sync_wait = 0;
 SET GLOBAL DEBUG_DBUG = "";
-SET DEBUG_SYNC = "now SIGNAL wsrep_after_replication_continue";
 SET DEBUG_SYNC = "now SIGNAL signal.wsrep_apply_cb";
 connection node_2;
 connection node_1;
diff --git a/mysql-test/suite/galera/r/galera_events2.result b/mysql-test/suite/galera/r/galera_events2.result
index fa33e75ff57..36441e15f7d 100644
--- a/mysql-test/suite/galera/r/galera_events2.result
+++ b/mysql-test/suite/galera/r/galera_events2.result
@@ -14,6 +14,7 @@ SELECT EVENT_CATALOG, EVENT_SCHEMA, EVENT_NAME, DEFINER, EVENT_BODY, EVENT_DEFIN
 EVENT_CATALOG	EVENT_SCHEMA	EVENT_NAME	DEFINER	EVENT_BODY	EVENT_DEFINITION	EVENT_TYPE	EXECUTE_AT	INTERVAL_VALUE	INTERVAL_FIELD	STATUS	ON_COMPLETION	EVENT_COMMENT
 def	test	event_2	root@localhost	SQL	INSERT INTO event_table VALUES (1)	RECURRING	NULL	1	SECOND	ENABLED	NOT PRESERVE	
 connection node_2;
+set global wsrep_sync_wait=15;
 # node_2 event should be there
 SELECT EVENT_CATALOG, EVENT_SCHEMA, EVENT_NAME, DEFINER, EVENT_BODY, EVENT_DEFINITION, EVENT_TYPE, EXECUTE_AT, INTERVAL_VALUE, INTERVAL_FIELD, STATUS,ON_COMPLETION, EVENT_COMMENT FROM INFORMATION_SCHEMA.EVENTS WHERE EVENT_NAME='event_2';
 EVENT_CATALOG	EVENT_SCHEMA	EVENT_NAME	DEFINER	EVENT_BODY	EVENT_DEFINITION	EVENT_TYPE	EXECUTE_AT	INTERVAL_VALUE	INTERVAL_FIELD	STATUS	ON_COMPLETION	EVENT_COMMENT
diff --git a/mysql-test/suite/galera/r/galera_ist_restart_joiner.result b/mysql-test/suite/galera/r/galera_ist_restart_joiner.result
index c81cecfae1c..d38d664b6fa 100644
--- a/mysql-test/suite/galera/r/galera_ist_restart_joiner.result
+++ b/mysql-test/suite/galera/r/galera_ist_restart_joiner.result
@@ -13,7 +13,6 @@ Loading wsrep_provider ...
 SET SESSION wsrep_on=OFF;
 SET SESSION wsrep_on=ON;
 connection node_1;
-connection node_1;
 UPDATE t1 SET f2 = 'd' WHERE f1 > 3;
 connection node_2;
 connection node_1;
diff --git a/mysql-test/suite/galera/t/MW-388.test b/mysql-test/suite/galera/t/MW-388.test
index 042b7e2fee5..09fc8a8bfc9 100644
--- a/mysql-test/suite/galera/t/MW-388.test
+++ b/mysql-test/suite/galera/t/MW-388.test
@@ -31,6 +31,8 @@ DELIMITER ;|
 SET GLOBAL wsrep_slave_threads = 2;
 SET GLOBAL DEBUG_DBUG = "d,sync.wsrep_apply_cb";
 
+--let $expected_cert_failures = `SELECT VARIABLE_VALUE + 1 FROM INFORMATION_SCHEMA.GLOBAL_STATUS WHERE VARIABLE_NAME = 'wsrep_local_cert_failures'`
+
 --connection node_2
 --send INSERT INTO t1 VALUES (1, 'node 2');
 
@@ -40,15 +42,15 @@ SET SESSION DEBUG_SYNC = "now WAIT_FOR sync.wsrep_apply_cb_reached";
 
 --connection node_1
 SET SESSION wsrep_sync_wait = 0;
-SET SESSION DEBUG_SYNC = 'wsrep_after_replication SIGNAL wsrep_after_replication_reached WAIT_FOR wsrep_after_replication_continue';
 --send CALL insert_proc ();
 
 --connection node_1a
-SET SESSION DEBUG_SYNC = "now WAIT_FOR wsrep_after_replication_reached";
+SET SESSION wsrep_sync_wait = 0;
+--let $wait_condition = SELECT VARIABLE_VALUE = $expected_cert_failures FROM INFORMATION_SCHEMA.GLOBAL_STATUS WHERE VARIABLE_NAME = 'wsrep_local_cert_failures'
+--source include/wait_condition.inc
 
 
 SET GLOBAL DEBUG_DBUG = "";
-SET DEBUG_SYNC = "now SIGNAL wsrep_after_replication_continue";
 SET DEBUG_SYNC = "now SIGNAL signal.wsrep_apply_cb";
 
 --connection node_2
diff --git a/mysql-test/suite/galera/t/galera_events2.test b/mysql-test/suite/galera/t/galera_events2.test
index 54b90386851..3dfbe406fc4 100644
--- a/mysql-test/suite/galera/t/galera_events2.test
+++ b/mysql-test/suite/galera/t/galera_events2.test
@@ -23,6 +23,7 @@ DO
 SELECT EVENT_CATALOG, EVENT_SCHEMA, EVENT_NAME, DEFINER, EVENT_BODY, EVENT_DEFINITION, EVENT_TYPE, EXECUTE_AT, INTERVAL_VALUE, INTERVAL_FIELD, STATUS,ON_COMPLETION, EVENT_COMMENT FROM INFORMATION_SCHEMA.EVENTS WHERE EVENT_NAME='event_2';
 
 --connection node_2
+set global wsrep_sync_wait=15;
 --echo # node_2 event should be there
 SELECT EVENT_CATALOG, EVENT_SCHEMA, EVENT_NAME, DEFINER, EVENT_BODY, EVENT_DEFINITION, EVENT_TYPE, EXECUTE_AT, INTERVAL_VALUE, INTERVAL_FIELD, STATUS,ON_COMPLETION, EVENT_COMMENT FROM INFORMATION_SCHEMA.EVENTS WHERE EVENT_NAME='event_2';
 
@@ -66,6 +67,9 @@ ALTER EVENT one_event ON SCHEDULE EVERY 10 SECOND;
 SELECT EVENT_CATALOG, EVENT_SCHEMA, EVENT_NAME, DEFINER, EVENT_BODY, EVENT_DEFINITION, EVENT_TYPE, EXECUTE_AT, INTERVAL_VALUE, INTERVAL_FIELD, STATUS,ON_COMPLETION, EVENT_COMMENT FROM INFORMATION_SCHEMA.EVENTS WHERE EVENT_NAME='one_event';
 
 --connection node_2
+--let $wait_condition = SELECT COUNT(*) = 1 FROM INFORMATION_SCHEMA.EVENTS WHERE EVENT_NAME='one_event';
+--source include/wait_condition.inc
+
 use events_test;
 --echo "The definer should be ev_test@localhost"
 SELECT EVENT_CATALOG, EVENT_SCHEMA, EVENT_NAME, DEFINER, EVENT_BODY, EVENT_DEFINITION, EVENT_TYPE, EXECUTE_AT, INTERVAL_VALUE, INTERVAL_FIELD, STATUS,ON_COMPLETION, EVENT_COMMENT FROM INFORMATION_SCHEMA.EVENTS WHERE EVENT_NAME='one_event';
diff --git a/mysql-test/suite/gcol/r/innodb_virtual_debug_purge.result b/mysql-test/suite/gcol/r/innodb_virtual_debug_purge.result
index d99565b2f4c..837f72129ca 100644
--- a/mysql-test/suite/gcol/r/innodb_virtual_debug_purge.result
+++ b/mysql-test/suite/gcol/r/innodb_virtual_debug_purge.result
@@ -208,7 +208,7 @@ DROP TABLE t1, t2;
 # MDEV-16222 Assertion `0' failed in row_purge_remove_sec_if_poss_leaf
 # on table with virtual columns and indexes
 #
-set @saved_dbug= @@global.debug_dbug;
+SET @saved_dbug= @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,ib_purge_virtual_mdev_16222_1,ib_purge_virtual_mdev_16222_2";
 create table t1 (
 pk serial, vb tinyblob as (b) virtual, b tinyblob,
@@ -253,7 +253,7 @@ SET GLOBAL innodb_debug_sync = "ib_clust_v_col_before_row_allocated "
 SET GLOBAL innodb_debug_sync = "ib_open_after_dict_open "
                                "SIGNAL purge_open "
                                "WAIT_FOR select_open";
-set @saved_dbug= @@global.debug_dbug;
+SET @saved_dbug= @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,ib_purge_virtual_index_callback";
 connect purge_waiter,localhost,root;
 SET debug_sync= "now WAIT_FOR before_row_allocated";
diff --git a/mysql-test/suite/gcol/t/innodb_virtual_debug_purge.test b/mysql-test/suite/gcol/t/innodb_virtual_debug_purge.test
index 276407007da..ca9d016fdcc 100644
--- a/mysql-test/suite/gcol/t/innodb_virtual_debug_purge.test
+++ b/mysql-test/suite/gcol/t/innodb_virtual_debug_purge.test
@@ -265,7 +265,7 @@ DROP TABLE t1, t2;
 --echo #
 
 --let $datadir= `select @@datadir`
-set @saved_dbug= @@global.debug_dbug;
+SET @saved_dbug= @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,ib_purge_virtual_mdev_16222_1,ib_purge_virtual_mdev_16222_2";
 
 create table t1 (
@@ -336,7 +336,7 @@ SET GLOBAL innodb_debug_sync = "ib_open_after_dict_open "
 
 # In 10.2 trx_undo_roll_ptr_is_insert(t_roll_ptr) condition never pass in purge,
 # so this condition is forced to pass in row_vers_old_has_index_entry
-set @saved_dbug= @@global.debug_dbug;
+SET @saved_dbug= @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,ib_purge_virtual_index_callback";
 
 # The purge starts from REPLACE command. To avoid possible race, separate
diff --git a/mysql-test/suite/innodb/r/blob-update-debug.result b/mysql-test/suite/innodb/r/blob-update-debug.result
index 1360745b7e6..813a469dd2b 100644
--- a/mysql-test/suite/innodb/r/blob-update-debug.result
+++ b/mysql-test/suite/innodb/r/blob-update-debug.result
@@ -7,9 +7,11 @@ insert into t1 values (1, repeat('*', 50000));
 select f1, substring(f2, 1, 40) from t1;
 f1	substring(f2, 1, 40)
 1	****************************************
-set debug_dbug = 'd,row_ins_index_entry_timeout';
+set @saved_debug = @@session.debug_dbug;
+SET debug_dbug = 'd,row_ins_index_entry_timeout';
 update t1 set f1 = 3;
 select f1, substring(f2, 1, 40) from t1;
 f1	substring(f2, 1, 40)
 3	****************************************
 drop table t1;
+SET debug_dbug= @saved_debug;
diff --git a/mysql-test/suite/innodb/r/innodb-replace-debug.result b/mysql-test/suite/innodb/r/innodb-replace-debug.result
index 989fb055cbc..03e22b774e4 100644
--- a/mysql-test/suite/innodb/r/innodb-replace-debug.result
+++ b/mysql-test/suite/innodb/r/innodb-replace-debug.result
@@ -5,10 +5,10 @@ create table t1 (f1 int primary key, f2 int, f3 int, unique key k1(f2),
 key k2(f3)) engine=innodb;
 insert into t1 values (14, 24, 34);
 set @old_dbug= @@session.debug_dbug;
-set debug_dbug = '+d,row_ins_sec_index_entry_timeout';
+SET debug_dbug = '+d,row_ins_sec_index_entry_timeout';
 replace into t1 values (14, 25, 34);
 select * from t1;
 f1	f2	f3
 14	25	34
 drop table t1;
-set debug_dbug = @old_dbug;
+SET debug_dbug = @old_dbug;
diff --git a/mysql-test/suite/innodb/r/innodb-stats-initialize-failure.result b/mysql-test/suite/innodb/r/innodb-stats-initialize-failure.result
index ef2d3182b92..06bb708b82c 100644
--- a/mysql-test/suite/innodb/r/innodb-stats-initialize-failure.result
+++ b/mysql-test/suite/innodb/r/innodb-stats-initialize-failure.result
@@ -1,4 +1,5 @@
 call mtr.add_suppression("InnoDB: Warning: Index.*");
+SET @saved_dbug = @@SESSION.debug_dbug;
 set DEBUG_DBUG='+d,ib_ha_innodb_stat_not_initialized';
 create table t1(a int not null primary key, b int, c int, key(b), key(c)) engine=innodb;
 create procedure innodb_insert_proc (repeat_count int)
@@ -27,6 +28,6 @@ count(1)
 select count(1) from t1 where c between 7 and 787;
 count(1)
 781
-set DEBUG_DBUG=NULL;
 drop procedure innodb_insert_proc;
 drop table t1;
+SET debug_dbug= @saved_dbug;
diff --git a/mysql-test/suite/innodb/r/innodb-wl5522-1.result b/mysql-test/suite/innodb/r/innodb-wl5522-1.result
index b2a5f49a9ad..55557a8fb99 100644
--- a/mysql-test/suite/innodb/r/innodb-wl5522-1.result
+++ b/mysql-test/suite/innodb/r/innodb-wl5522-1.result
@@ -389,7 +389,7 @@ CREATE TABLE testdb_wl5522.t1 ( i bigint) ENGINE = Innodb;
 ALTER TABLE testdb_wl5522.t1 DISCARD TABLESPACE;
 restore: t1 .ibd and .cfg files
 ALTER TABLE testdb_wl5522.t1 IMPORT TABLESPACE;
-ERROR HY000: Schema mismatch (Column i precise type mismatch.)
+ERROR HY000: Schema mismatch (Column i precise type mismatch, it's 0X408 in the table and 0X403 in the tablespace meta file)
 unlink: t1.ibd
 unlink: t1.cfg
 DROP TABLE testdb_wl5522.t1;
diff --git a/mysql-test/suite/innodb/r/innodb-wl5522.result b/mysql-test/suite/innodb/r/innodb-wl5522.result
index 62f03292baa..b364b36a36f 100644
--- a/mysql-test/suite/innodb/r/innodb-wl5522.result
+++ b/mysql-test/suite/innodb/r/innodb-wl5522.result
@@ -426,7 +426,7 @@ SELECT * FROM t1;
 ERROR HY000: Tablespace has been discarded for table `t1`
 restore: t1 .ibd and .cfg files
 ALTER TABLE t1 IMPORT TABLESPACE;
-ERROR HY000: Schema mismatch (Column c2 precise type mismatch.)
+ERROR HY000: Schema mismatch (Column c2 precise type mismatch, it's 0X408 in the table and 0X403 in the tablespace meta file)
 unlink: t1.ibd
 unlink: t1.cfg
 DROP TABLE t1;
diff --git a/mysql-test/suite/innodb/r/innodb_bug11754376.result b/mysql-test/suite/innodb/r/innodb_bug11754376.result
index b9f2a169a73..650dfbb35c2 100644
--- a/mysql-test/suite/innodb/r/innodb_bug11754376.result
+++ b/mysql-test/suite/innodb/r/innodb_bug11754376.result
@@ -1,3 +1,5 @@
 CREATE TABLE bug11754376 (c INT) ENGINE=INNODB;
+SET @saved_dbug = @@SESSION.debug_dbug;
 SET SESSION DEBUG_DBUG='+d,test_normalize_table_name_low';
 DROP TABLE bug11754376;
+SET debug_dbug= @saved_dbug;
diff --git a/mysql-test/suite/innodb/r/innodb_bug56947.result b/mysql-test/suite/innodb/r/innodb_bug56947.result
index 4248013b088..aa922776f7b 100644
--- a/mysql-test/suite/innodb/r/innodb_bug56947.result
+++ b/mysql-test/suite/innodb/r/innodb_bug56947.result
@@ -1,5 +1,6 @@
 SET GLOBAL innodb_file_per_table=0;
 create table bug56947(a int not null) engine = innodb;
+SET @saved_dbug = @@SESSION.debug_dbug;
 SET DEBUG_DBUG='+d,ib_rebuild_cannot_rename';
 alter table bug56947 add unique index (a);
 ERROR HY000: Got error 11 "xxx" from storage engine InnoDB
@@ -8,3 +9,4 @@ Table	Op	Msg_type	Msg_text
 test.bug56947	check	status	OK
 drop table bug56947;
 SET @@global.innodb_file_per_table=DEFAULT;
+SET debug_dbug= @saved_dbug;
diff --git a/mysql-test/suite/innodb/r/innodb_corrupt_bit.result b/mysql-test/suite/innodb/r/innodb_corrupt_bit.result
index 2000db03efa..daf0345e8ca 100644
--- a/mysql-test/suite/innodb/r/innodb_corrupt_bit.result
+++ b/mysql-test/suite/innodb/r/innodb_corrupt_bit.result
@@ -24,7 +24,7 @@ test.corrupt_bit_test_ā	check	Warning	InnoDB: Index idx is marked as corrupted
 test.corrupt_bit_test_ā	check	Warning	InnoDB: Index idxā is marked as corrupted
 test.corrupt_bit_test_ā	check	Warning	InnoDB: Index idxē is marked as corrupted
 test.corrupt_bit_test_ā	check	error	Corrupt
-SET debug_dbug = @save_dbug;
+SET @@SESSION.debug_dbug = @save_dbug;
 CREATE INDEX idx3 ON corrupt_bit_test_ā(b, c);
 ERROR HY000: Index idx is corrupted
 CREATE INDEX idx4 ON corrupt_bit_test_ā(b, z);
diff --git a/mysql-test/suite/innodb/r/innodb_sys_semaphore_waits.result b/mysql-test/suite/innodb/r/innodb_sys_semaphore_waits.result
index 5f14ad9b0d7..65d0a0bde43 100644
--- a/mysql-test/suite/innodb/r/innodb_sys_semaphore_waits.result
+++ b/mysql-test/suite/innodb/r/innodb_sys_semaphore_waits.result
@@ -4,6 +4,7 @@ drop table if exists t1;
 connection con1;
 create table t1 (id integer, x integer) engine = InnoDB;
 insert into t1 values(0, 0);
+SET @saved_dbug = @@SESSION.debug_dbug;
 set DEBUG_DBUG='+d,fatal-semaphore-timeout';
 set autocommit=0;
 # Sending query on con1,
@@ -21,6 +22,6 @@ connection default;
 # Waitting for reconnect after mysqld restarts
 # Reconnected after mysqld was successfully restarted
 # Cleaning up before exit
-set DEBUG_DBUG=NULL;
+SET debug_dbug = @saved_dbug;
 drop table if exists t1;
 # Clean exit
diff --git a/mysql-test/suite/innodb/r/redo_log_during_checkpoint.result b/mysql-test/suite/innodb/r/redo_log_during_checkpoint.result
index efe48682a6f..3915b07f12e 100644
--- a/mysql-test/suite/innodb/r/redo_log_during_checkpoint.result
+++ b/mysql-test/suite/innodb/r/redo_log_during_checkpoint.result
@@ -4,8 +4,8 @@ SET GLOBAL innodb_master_thread_disabled_debug = 1;
 SET GLOBAL innodb_log_checkpoint_now = 1;
 CREATE DATABASE very_long_database_name;
 USE very_long_database_name;
-set debug_dbug = '+d,increase_mtr_checkpoint_size';
-set debug_dbug = '+d,crash_after_checkpoint';
+SET debug_dbug = '+d,increase_mtr_checkpoint_size';
+SET debug_dbug = '+d,crash_after_checkpoint';
 set global innodb_log_checkpoint_now = 1;
 ERROR HY000: Lost connection to MySQL server during query
 # Skip MLOG_FILE_NAME redo records during recovery
@@ -18,7 +18,7 @@ SET GLOBAL innodb_log_checkpoint_now = 1;
 # exceeds LOG_CHECKPOINT_FREE_PER_THREAD size during checkpoint.
 CREATE DATABASE very_long_database_name;
 USE very_long_database_name;
-set debug_dbug = '+d,crash_after_checkpoint';
+SET debug_dbug = '+d,crash_after_checkpoint';
 set global innodb_log_checkpoint_now = 1;
 ERROR HY000: Lost connection to MySQL server during query
 # Skip MLOG_FILE_NAME redo records during recovery
diff --git a/mysql-test/suite/innodb/t/blob-update-debug.test b/mysql-test/suite/innodb/t/blob-update-debug.test
index 948cd749148..8d35dbfc70e 100644
--- a/mysql-test/suite/innodb/t/blob-update-debug.test
+++ b/mysql-test/suite/innodb/t/blob-update-debug.test
@@ -11,7 +11,9 @@
 create table t1 (f1 int primary key, f2 blob) engine = innodb;
 insert into t1 values (1, repeat('*', 50000));
 select f1, substring(f2, 1, 40) from t1;
-set debug_dbug = 'd,row_ins_index_entry_timeout';
+set @saved_debug = @@session.debug_dbug;
+SET debug_dbug = 'd,row_ins_index_entry_timeout';
 update t1 set f1 = 3;
 select f1, substring(f2, 1, 40) from t1;
 drop table t1;
+SET debug_dbug= @saved_debug;
diff --git a/mysql-test/suite/innodb/t/innodb-replace-debug.test b/mysql-test/suite/innodb/t/innodb-replace-debug.test
index 7e710ae154c..823712a01f1 100644
--- a/mysql-test/suite/innodb/t/innodb-replace-debug.test
+++ b/mysql-test/suite/innodb/t/innodb-replace-debug.test
@@ -9,8 +9,8 @@ create table t1 (f1 int primary key, f2 int, f3 int, unique key k1(f2),
   key k2(f3)) engine=innodb;
 insert into t1 values (14, 24, 34);
 set @old_dbug= @@session.debug_dbug;
-set debug_dbug = '+d,row_ins_sec_index_entry_timeout';
+SET debug_dbug = '+d,row_ins_sec_index_entry_timeout';
 replace into t1 values (14, 25, 34);
 select * from t1;
 drop table t1;
-set debug_dbug = @old_dbug;
+SET debug_dbug = @old_dbug;
diff --git a/mysql-test/suite/innodb/t/innodb-stats-initialize-failure.test b/mysql-test/suite/innodb/t/innodb-stats-initialize-failure.test
index e480f0caf07..d5d04190b8a 100644
--- a/mysql-test/suite/innodb/t/innodb-stats-initialize-failure.test
+++ b/mysql-test/suite/innodb/t/innodb-stats-initialize-failure.test
@@ -6,6 +6,7 @@
 
 call mtr.add_suppression("InnoDB: Warning: Index.*");
 # This caused crash earlier
+SET @saved_dbug = @@SESSION.debug_dbug;
 set DEBUG_DBUG='+d,ib_ha_innodb_stat_not_initialized';
 create table t1(a int not null primary key, b int, c int, key(b), key(c)) engine=innodb;
 
@@ -32,8 +33,8 @@ select count(1) from t1 where a between 5 and 100;
 select count(1) from t1 where b between 5 and 256;
 select count(1) from t1 where c between 7 and 787;
 
-set DEBUG_DBUG=NULL;
+
 
 drop procedure innodb_insert_proc;
 drop table t1;
-
+SET debug_dbug= @saved_dbug;
diff --git a/mysql-test/suite/innodb/t/innodb_bug11754376.test b/mysql-test/suite/innodb/t/innodb_bug11754376.test
index a7f35c1a960..64547d409b3 100644
--- a/mysql-test/suite/innodb/t/innodb_bug11754376.test
+++ b/mysql-test/suite/innodb/t/innodb_bug11754376.test
@@ -8,7 +8,8 @@
 CREATE TABLE bug11754376 (c INT) ENGINE=INNODB;
 
 # This will invoke test_normalize_table_name_low() in debug builds
-
+SET @saved_dbug = @@SESSION.debug_dbug;
 SET SESSION DEBUG_DBUG='+d,test_normalize_table_name_low';
 
 DROP TABLE bug11754376;
+SET debug_dbug= @saved_dbug;
diff --git a/mysql-test/suite/innodb/t/innodb_bug56947.test b/mysql-test/suite/innodb/t/innodb_bug56947.test
index 84c5e70e1b5..ce64f1a8322 100644
--- a/mysql-test/suite/innodb/t/innodb_bug56947.test
+++ b/mysql-test/suite/innodb/t/innodb_bug56947.test
@@ -7,6 +7,7 @@
 SET GLOBAL innodb_file_per_table=0;
 create table bug56947(a int not null) engine = innodb;
 
+SET @saved_dbug = @@SESSION.debug_dbug;
 SET DEBUG_DBUG='+d,ib_rebuild_cannot_rename';
 --replace_regex /"[^"]*"/"xxx"/
 --error ER_GET_ERRNO
@@ -15,3 +16,4 @@ check table bug56947;
 
 drop table bug56947;
 SET @@global.innodb_file_per_table=DEFAULT;
+SET debug_dbug= @saved_dbug;
diff --git a/mysql-test/suite/innodb/t/innodb_corrupt_bit.test b/mysql-test/suite/innodb/t/innodb_corrupt_bit.test
index 1d723c0bbc3..f1fd7f3c56a 100644
--- a/mysql-test/suite/innodb/t/innodb_corrupt_bit.test
+++ b/mysql-test/suite/innodb/t/innodb_corrupt_bit.test
@@ -36,7 +36,7 @@ select count(*) from corrupt_bit_test_ā;
 SET @save_dbug = @@SESSION.debug_dbug;
 SET debug_dbug = '+d,dict_set_index_corrupted';
 check table corrupt_bit_test_ā;
-SET debug_dbug = @save_dbug;
+SET @@SESSION.debug_dbug = @save_dbug;
 
 # Cannot create new indexes while corrupted indexes exist
 --error ER_INDEX_CORRUPT
diff --git a/mysql-test/suite/innodb/t/innodb_sys_semaphore_waits.test b/mysql-test/suite/innodb/t/innodb_sys_semaphore_waits.test
index e7acb98b0d0..ccd9e3d70f4 100644
--- a/mysql-test/suite/innodb/t/innodb_sys_semaphore_waits.test
+++ b/mysql-test/suite/innodb/t/innodb_sys_semaphore_waits.test
@@ -17,6 +17,7 @@ eval create table t1 (id integer, x integer) engine = InnoDB;
 insert into t1 values(0, 0);
 
 # Enable the debug injection.
+SET @saved_dbug = @@SESSION.debug_dbug;
 set DEBUG_DBUG='+d,fatal-semaphore-timeout';
 set autocommit=0;
 
@@ -107,7 +108,7 @@ source include/wait_until_connected_again.inc;
 
 --echo # Cleaning up before exit
 --disable_warnings
-set DEBUG_DBUG=NULL;
+SET debug_dbug = @saved_dbug;
 drop table if exists t1;
 --enable_warnings
 
diff --git a/mysql-test/suite/innodb/t/redo_log_during_checkpoint.test b/mysql-test/suite/innodb/t/redo_log_during_checkpoint.test
index 9ff01739f60..f1d1537237e 100644
--- a/mysql-test/suite/innodb/t/redo_log_during_checkpoint.test
+++ b/mysql-test/suite/innodb/t/redo_log_during_checkpoint.test
@@ -33,8 +33,8 @@ while ($i)
 --let $_expect_file_name= $MYSQLTEST_VARDIR/tmp/mysqld.$_server_id.expect
 --exec echo "wait" > $_expect_file_name
 
-set debug_dbug = '+d,increase_mtr_checkpoint_size';
-set debug_dbug = '+d,crash_after_checkpoint';
+SET debug_dbug = '+d,increase_mtr_checkpoint_size';
+SET debug_dbug = '+d,crash_after_checkpoint';
 --error 2013
 set global innodb_log_checkpoint_now = 1;
 
@@ -64,7 +64,7 @@ while ($i)
 --enable_query_log
 
 --exec echo "wait" > $_expect_file_name
-set debug_dbug = '+d,crash_after_checkpoint';
+SET debug_dbug = '+d,crash_after_checkpoint';
 --error 2013
 set global innodb_log_checkpoint_now = 1;
 
diff --git a/mysql-test/suite/innodb_fts/r/concurrent_insert.result b/mysql-test/suite/innodb_fts/r/concurrent_insert.result
index 9871d43119a..9be7ba35f30 100644
--- a/mysql-test/suite/innodb_fts/r/concurrent_insert.result
+++ b/mysql-test/suite/innodb_fts/r/concurrent_insert.result
@@ -17,6 +17,7 @@ INSERT INTO t1 VALUES('test');
 CREATE TABLE t2 (f1 char(100), FULLTEXT idx1(f1))ENGINE=InnoDB;
 INSERT INTO t2 VALUES('mariadb');
 connection default;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 SET GLOBAL debug_dbug ='+d,fts_instrument_sync_request,ib_optimize_wq_hang';
 SET DEBUG_SYNC= 'fts_instrument_sync_request
 		 SIGNAL drop_index_start WAIT_FOR sync_op';
@@ -28,7 +29,7 @@ ALTER TABLE t2 drop index idx1;
 connection default;
 set DEBUG_SYNC= 'now SIGNAL fts_drop_index';
 connection con1;
-SET global DEBUG_DBUG=RESET;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 drop table t1, t2;
 connection default;
 set DEBUG_SYNC=RESET;
diff --git a/mysql-test/suite/innodb_fts/t/concurrent_insert.test b/mysql-test/suite/innodb_fts/t/concurrent_insert.test
index 77097d44dc5..1505767d835 100644
--- a/mysql-test/suite/innodb_fts/t/concurrent_insert.test
+++ b/mysql-test/suite/innodb_fts/t/concurrent_insert.test
@@ -29,6 +29,7 @@ CREATE TABLE t2 (f1 char(100), FULLTEXT idx1(f1))ENGINE=InnoDB;
 INSERT INTO t2 VALUES('mariadb');
 
 connection default;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 SET GLOBAL debug_dbug ='+d,fts_instrument_sync_request,ib_optimize_wq_hang';
 SET DEBUG_SYNC= 'fts_instrument_sync_request
 		 SIGNAL drop_index_start WAIT_FOR sync_op';
@@ -45,7 +46,7 @@ set DEBUG_SYNC= 'now SIGNAL fts_drop_index';
 
 connection con1;
 reap;
-SET global DEBUG_DBUG=RESET;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 drop table t1, t2;
 connection default;
 set DEBUG_SYNC=RESET;
diff --git a/mysql-test/suite/innodb_gis/r/rtree_debug.result b/mysql-test/suite/innodb_gis/r/rtree_debug.result
index 11e2cd40e25..e8d2418af57 100644
--- a/mysql-test/suite/innodb_gis/r/rtree_debug.result
+++ b/mysql-test/suite/innodb_gis/r/rtree_debug.result
@@ -42,7 +42,7 @@ SET @save_dbug = @@SESSION.debug_dbug;
 SET debug_dbug='+d,row_merge_ins_spatial_fail';
 create spatial index idx2 on t1(c2);
 ERROR HY000: Got error 1000 "Unknown error 1000" from storage engine InnoDB
-SET debug_dbug = @save_dbug;
+SET @@SESSION.debug_dbug = @save_dbug;
 show create table t1;
 Table	Create Table
 t1	CREATE TABLE `t1` (
diff --git a/mysql-test/suite/innodb_gis/t/rtree_debug.test b/mysql-test/suite/innodb_gis/t/rtree_debug.test
index 2f7c2806c68..580f3cf48a1 100644
--- a/mysql-test/suite/innodb_gis/t/rtree_debug.test
+++ b/mysql-test/suite/innodb_gis/t/rtree_debug.test
@@ -53,7 +53,7 @@ SET @save_dbug = @@SESSION.debug_dbug;
 SET debug_dbug='+d,row_merge_ins_spatial_fail';
 --error ER_GET_ERRNO
 create spatial index idx2 on t1(c2);
-SET debug_dbug = @save_dbug;
+SET @@SESSION.debug_dbug = @save_dbug;
 show create table t1;
 
 # Check table.
diff --git a/mysql-test/suite/innodb_zip/r/wl5522_zip.result b/mysql-test/suite/innodb_zip/r/wl5522_zip.result
index f57e2191d9f..a8e06835d85 100644
--- a/mysql-test/suite/innodb_zip/r/wl5522_zip.result
+++ b/mysql-test/suite/innodb_zip/r/wl5522_zip.result
@@ -410,7 +410,7 @@ SELECT * FROM t1;
 ERROR HY000: Tablespace has been discarded for table `t1`
 restore: t1 .ibd and .cfg files
 ALTER TABLE t1 IMPORT TABLESPACE;
-ERROR HY000: Schema mismatch (Column c2 precise type mismatch.)
+ERROR HY000: Schema mismatch (Column c2 precise type mismatch, it's 0X408 in the table and 0X403 in the tablespace meta file)
 unlink: t1.ibd
 unlink: t1.cfg
 DROP TABLE t1;
diff --git a/mysql-test/suite/optimizer_unfixed_bugs/r/bug36981.result b/mysql-test/suite/optimizer_unfixed_bugs/r/bug36981.result
index 760d7342752..a0be9e23818 100644
--- a/mysql-test/suite/optimizer_unfixed_bugs/r/bug36981.result
+++ b/mysql-test/suite/optimizer_unfixed_bugs/r/bug36981.result
@@ -1,3 +1,4 @@
+SET @saved_dbug = @@SESSION.debug_dbug;
 set session debug_dbug="+d,optimizer_innodb_icp";
 create table `t1` (`c1` char(1) default null,`c2` char(10) default null,
 key (`c1`))
@@ -7,3 +8,4 @@ select * from `t1` where `c1`='3' for update;
 c1	c2
 3	NULL
 drop table `t1`;
+SET debug_dbug= @saved_dbug;
diff --git a/mysql-test/suite/optimizer_unfixed_bugs/r/bug40992.result b/mysql-test/suite/optimizer_unfixed_bugs/r/bug40992.result
index 5e53649c538..59ab7607a40 100644
--- a/mysql-test/suite/optimizer_unfixed_bugs/r/bug40992.result
+++ b/mysql-test/suite/optimizer_unfixed_bugs/r/bug40992.result
@@ -1,6 +1,7 @@
 #
 # Bug#40992 - InnoDB: Crash when engine_condition_pushdown is on
 #
+SET @saved_dbug = @@SESSION.debug_dbug;
 set session debug_dbug="+d,optimizer_innodb_icp";
 CREATE TABLE t (
 dummy INT PRIMARY KEY, 
@@ -13,3 +14,4 @@ dummy	a	b
 3	3	3
 5	5	5
 DROP TABLE t;
+SET debug_dbug= @saved_dbug;
diff --git a/mysql-test/suite/optimizer_unfixed_bugs/r/bug41996.result b/mysql-test/suite/optimizer_unfixed_bugs/r/bug41996.result
index 31e39d4421d..acc18b06ea0 100644
--- a/mysql-test/suite/optimizer_unfixed_bugs/r/bug41996.result
+++ b/mysql-test/suite/optimizer_unfixed_bugs/r/bug41996.result
@@ -1,3 +1,4 @@
+SET @saved_dbug = @@SESSION.debug_dbug;
 set session debug_dbug="+d,optimizer_innodb_icp";
 drop table if exists `t1`;
 Warnings:
@@ -6,3 +7,4 @@ create table `t1` (`c` bigint, key(`c`),`a` int)engine=innodb;
 insert into `t1` values(2,2);
 delete `t1` from `t1` `a`, `t1` where `a`.`a`=`t1`.`c` ;
 drop table `t1`;
+SET debug_dbug= @saved_dbug;
diff --git a/mysql-test/suite/optimizer_unfixed_bugs/r/bug42991.result b/mysql-test/suite/optimizer_unfixed_bugs/r/bug42991.result
index e4fdf0d03a7..f5554563a18 100644
--- a/mysql-test/suite/optimizer_unfixed_bugs/r/bug42991.result
+++ b/mysql-test/suite/optimizer_unfixed_bugs/r/bug42991.result
@@ -1,3 +1,4 @@
+SET @saved_dbug = @@SESSION.debug_dbug;
 set session debug_dbug="+d,optimizer_innodb_icp";
 /*!40101 SET @OLD_CHARACTER_SET_CLIENT=@@CHARACTER_SET_CLIENT */;
 /*!40101 SET @OLD_CHARACTER_SET_RESULTS=@@CHARACTER_SET_RESULTS */;
@@ -252,3 +253,4 @@ Warning	1292	Truncated incorrect DOUBLE value: 'd'
 Warning	1292	Truncated incorrect DOUBLE value: 'd'
 Warning	1292	Truncated incorrect DOUBLE value: 'd'
 drop table `table5`;
+SET debug_dbug= @saved_dbug;
diff --git a/mysql-test/suite/optimizer_unfixed_bugs/r/bug43249.result b/mysql-test/suite/optimizer_unfixed_bugs/r/bug43249.result
index 0cd801280c8..f6f5cd7c6fd 100644
--- a/mysql-test/suite/optimizer_unfixed_bugs/r/bug43249.result
+++ b/mysql-test/suite/optimizer_unfixed_bugs/r/bug43249.result
@@ -1,3 +1,4 @@
+SET @saved_dbug = @@SESSION.debug_dbug;
 set session debug_dbug="+d,optimizer_innodb_icp";
 CREATE TABLE t1(c1 TIME NOT NULL, c2 TIME NULL, c3 DATE, PRIMARY
 KEY(c1), UNIQUE INDEX(c2)) engine=innodb;
@@ -9,3 +10,4 @@ SELECT * FROM t1 WHERE c2 <=> NULL ORDER BY c2 LIMIT 2;
 c1	c2	c3
 08:29:45	NULL	2009-02-01
 drop table `t1`;
+SET debug_dbug= @saved_dbug;
diff --git a/mysql-test/suite/optimizer_unfixed_bugs/r/bug43360.result b/mysql-test/suite/optimizer_unfixed_bugs/r/bug43360.result
index 899bf04e635..7e838906114 100644
--- a/mysql-test/suite/optimizer_unfixed_bugs/r/bug43360.result
+++ b/mysql-test/suite/optimizer_unfixed_bugs/r/bug43360.result
@@ -1,6 +1,7 @@
 #
 # Bug#43360 - Server crash with a simple multi-table update
 #
+SET @saved_dbug = @@SESSION.debug_dbug;
 set session debug_dbug="+d,optimizer_innodb_icp";
 CREATE TABLE t1 (
 a CHAR(2) NOT NULL PRIMARY KEY, 
@@ -42,3 +43,4 @@ AB	Sweden
 MS	United States of Ame
 JA	USA
 DROP TABLE t1,t2;
+SET debug_dbug= @saved_dbug;
diff --git a/mysql-test/suite/optimizer_unfixed_bugs/r/bug43448.result b/mysql-test/suite/optimizer_unfixed_bugs/r/bug43448.result
index a8f56923386..9b7a2c459c3 100644
--- a/mysql-test/suite/optimizer_unfixed_bugs/r/bug43448.result
+++ b/mysql-test/suite/optimizer_unfixed_bugs/r/bug43448.result
@@ -1,6 +1,7 @@
 #
 # Bug#43448 - Server crashes on multi table delete with Innodb
 #
+SET @saved_dbug = @@SESSION.debug_dbug;
 set session debug_dbug="+d,optimizer_innodb_icp";
 CREATE TABLE t1 (
 id1 INT NOT NULL AUTO_INCREMENT PRIMARY KEY, 
@@ -28,3 +29,4 @@ DELETE t1, t2, t3
 FROM t1, t2, t3 
 WHERE t1.id1 = t2.id2 AND t2.id2 = t3.id3 AND t1.id1 > 5;
 DROP TABLE t1, t2, t3;
+SET debug_dbug= @saved_dbug;
diff --git a/mysql-test/suite/optimizer_unfixed_bugs/r/bug43617.result b/mysql-test/suite/optimizer_unfixed_bugs/r/bug43617.result
index 0d88ff3d2cb..11f915aaf8e 100644
--- a/mysql-test/suite/optimizer_unfixed_bugs/r/bug43617.result
+++ b/mysql-test/suite/optimizer_unfixed_bugs/r/bug43617.result
@@ -1,6 +1,7 @@
 set storage_engine=innodb;
 set @save_time_zone= @@time_zone;
 set time_zone='+03:00';
+SET @saved_dbug = @@SESSION.debug_dbug;
 set session debug_dbug="+d,optimizer_innodb_icp";
 CREATE TABLE t1(c1 TIMESTAMP NOT NULL, c2 TIMESTAMP NULL, c3 DATE, c4 DATETIME, PRIMARY KEY(c1), UNIQUE INDEX(c2));
 INSERT INTO t1 VALUES('98-12-31 11:30:45','98.12.31 11+30+45','98-12-31 11:30:45','98.12.31 11+30+45'),('98/12/30 11*30*45','98@12@30 11^30^45','98/12/30 11*30*45','98@12@30 11^30^45'),('98-12-29','98.12.29','98-12-29','98.12.29'),('98/12/28','98@12@28','98/12/28','98@12@28');
@@ -100,3 +101,4 @@ c1	c2	c3	c4
 2038-01-09 03:14:07	2038-01-09 03:14:07	2009-01-05	2009-01-06 00:00:00
 DROP TABLE t1;
 set time_zone= @save_time_zone;
+SET debug_dbug= @saved_dbug;
diff --git a/mysql-test/suite/optimizer_unfixed_bugs/t/bug36981.test b/mysql-test/suite/optimizer_unfixed_bugs/t/bug36981.test
index da9de306b09..5c316c0a4d6 100644
--- a/mysql-test/suite/optimizer_unfixed_bugs/t/bug36981.test
+++ b/mysql-test/suite/optimizer_unfixed_bugs/t/bug36981.test
@@ -4,6 +4,7 @@
 --source include/have_innodb.inc
 
 # crash requires this
+SET @saved_dbug = @@SESSION.debug_dbug;
 set session debug_dbug="+d,optimizer_innodb_icp";
 
 create table `t1` (`c1` char(1) default null,`c2` char(10) default null,
@@ -12,3 +13,4 @@ engine=innodb default charset=latin1;
 insert into `t1` values ('3',null);
 select * from `t1` where `c1`='3' for update;
 drop table `t1`;
+SET debug_dbug= @saved_dbug;
diff --git a/mysql-test/suite/optimizer_unfixed_bugs/t/bug40992.test b/mysql-test/suite/optimizer_unfixed_bugs/t/bug40992.test
index b16f55aa951..41d38445095 100644
--- a/mysql-test/suite/optimizer_unfixed_bugs/t/bug40992.test
+++ b/mysql-test/suite/optimizer_unfixed_bugs/t/bug40992.test
@@ -5,6 +5,7 @@
 --source include/have_debug.inc
 --source include/have_innodb.inc
 
+SET @saved_dbug = @@SESSION.debug_dbug;
 # Crash requires that we enable Index Condition Pushdown in InnoDB
 set session debug_dbug="+d,optimizer_innodb_icp";
 
@@ -19,3 +20,4 @@ INSERT INTO t VALUES (1,1,1),(3,3,3),(5,5,5);
 SELECT * FROM t WHERE a > 2 FOR UPDATE;
 
 DROP TABLE t;
+SET debug_dbug= @saved_dbug;
diff --git a/mysql-test/suite/optimizer_unfixed_bugs/t/bug41996.test b/mysql-test/suite/optimizer_unfixed_bugs/t/bug41996.test
index 7d6237fa536..0eb7e34a9dd 100644
--- a/mysql-test/suite/optimizer_unfixed_bugs/t/bug41996.test
+++ b/mysql-test/suite/optimizer_unfixed_bugs/t/bug41996.test
@@ -5,6 +5,7 @@
 --source include/have_innodb.inc
 
 # crash requires this
+SET @saved_dbug = @@SESSION.debug_dbug;
 set session debug_dbug="+d,optimizer_innodb_icp";
 
 drop table if exists `t1`;
@@ -12,3 +13,4 @@ create table `t1` (`c` bigint, key(`c`),`a` int)engine=innodb;
 insert into `t1` values(2,2);
 delete `t1` from `t1` `a`, `t1` where `a`.`a`=`t1`.`c` ;
 drop table `t1`;
+SET debug_dbug= @saved_dbug;
diff --git a/mysql-test/suite/optimizer_unfixed_bugs/t/bug42991.test b/mysql-test/suite/optimizer_unfixed_bugs/t/bug42991.test
index 2b5864a3e69..d59e9e1fbeb 100644
--- a/mysql-test/suite/optimizer_unfixed_bugs/t/bug42991.test
+++ b/mysql-test/suite/optimizer_unfixed_bugs/t/bug42991.test
@@ -6,6 +6,7 @@
 
 --source include/have_innodb.inc
 
+SET @saved_dbug = @@SESSION.debug_dbug;
 # Valgrind errors happen only with this:
 set session debug_dbug="+d,optimizer_innodb_icp";
 
@@ -246,3 +247,4 @@ UNLOCK TABLES;
 select * from `table5` where  (col2 <= '6566-06-15' AND col24 <> 'd')  group by `col83` order by `col83` desc  ;
 
 drop table `table5`;
+SET debug_dbug= @saved_dbug;
diff --git a/mysql-test/suite/optimizer_unfixed_bugs/t/bug43249.test b/mysql-test/suite/optimizer_unfixed_bugs/t/bug43249.test
index 6275038a650..c647b777059 100644
--- a/mysql-test/suite/optimizer_unfixed_bugs/t/bug43249.test
+++ b/mysql-test/suite/optimizer_unfixed_bugs/t/bug43249.test
@@ -4,6 +4,7 @@
 --source include/have_debug.inc
 --source include/have_innodb.inc
 
+SET @saved_dbug = @@SESSION.debug_dbug;
 set session debug_dbug="+d,optimizer_innodb_icp";
 
 CREATE TABLE t1(c1 TIME NOT NULL, c2 TIME NULL, c3 DATE, PRIMARY
@@ -15,3 +16,4 @@ SELECT * FROM t1 WHERE c2 <=> NULL ORDER BY c2 LIMIT 2;
 SELECT * FROM t1 WHERE c2 <=> NULL ORDER BY c2 LIMIT 2;
 
 drop table `t1`;
+SET debug_dbug= @saved_dbug;
diff --git a/mysql-test/suite/optimizer_unfixed_bugs/t/bug43360.test b/mysql-test/suite/optimizer_unfixed_bugs/t/bug43360.test
index 9bfff0ccdb7..0896caa7712 100644
--- a/mysql-test/suite/optimizer_unfixed_bugs/t/bug43360.test
+++ b/mysql-test/suite/optimizer_unfixed_bugs/t/bug43360.test
@@ -6,6 +6,7 @@
 --source include/have_debug.inc
 --source include/have_innodb.inc
 
+SET @saved_dbug = @@SESSION.debug_dbug;
 # crash requires this
 set session debug_dbug="+d,optimizer_innodb_icp";
 
@@ -42,3 +43,4 @@ SELECT * FROM t1;
 SELECT * FROM t2;
 
 DROP TABLE t1,t2;   
+SET debug_dbug= @saved_dbug;
diff --git a/mysql-test/suite/optimizer_unfixed_bugs/t/bug43448.test b/mysql-test/suite/optimizer_unfixed_bugs/t/bug43448.test
index f7f40a6d3bf..4e1df63b45b 100644
--- a/mysql-test/suite/optimizer_unfixed_bugs/t/bug43448.test
+++ b/mysql-test/suite/optimizer_unfixed_bugs/t/bug43448.test
@@ -5,6 +5,7 @@
 --source include/have_debug.inc
 --source include/have_innodb.inc
 
+SET @saved_dbug = @@SESSION.debug_dbug;
 # crash requires ICP support in InnoDB
 set session debug_dbug="+d,optimizer_innodb_icp";
 
@@ -58,3 +59,4 @@ FROM t1, t2, t3
 WHERE t1.id1 = t2.id2 AND t2.id2 = t3.id3 AND t1.id1 > 5;
 
 DROP TABLE t1, t2, t3;
+SET debug_dbug= @saved_dbug;
diff --git a/mysql-test/suite/optimizer_unfixed_bugs/t/bug43617.test b/mysql-test/suite/optimizer_unfixed_bugs/t/bug43617.test
index 2b5b5fd96dd..02d0ab6d566 100644
--- a/mysql-test/suite/optimizer_unfixed_bugs/t/bug43617.test
+++ b/mysql-test/suite/optimizer_unfixed_bugs/t/bug43617.test
@@ -6,6 +6,7 @@
 set storage_engine=innodb;
 set @save_time_zone= @@time_zone;
 set time_zone='+03:00';
+SET @saved_dbug = @@SESSION.debug_dbug;
 set session debug_dbug="+d,optimizer_innodb_icp";
 
 ######## Running INSERT tests for TIMESTAMP ########
@@ -83,4 +84,4 @@ SELECT * FROM t1 WHERE c2 IN ('1971-01-01 00:00:01','2038-01-09 03:14:07') ORDER
 DROP TABLE t1;
 
 set time_zone= @save_time_zone;
-
+SET debug_dbug= @saved_dbug;
diff --git a/mysql-test/suite/parts/r/partition_debug.result b/mysql-test/suite/parts/r/partition_debug.result
index 7460fe8dd74..e438cae7a14 100644
--- a/mysql-test/suite/parts/r/partition_debug.result
+++ b/mysql-test/suite/parts/r/partition_debug.result
@@ -6,11 +6,11 @@ CREATE TABLE t1 (a INT, b VARCHAR(64), KEY(b,a))
 PARTITION BY HASH (a) PARTITIONS 3;
 INSERT INTO t1 VALUES (1, "1"), (2, "2"), (3, "3"), (4, "Four"), (5, "Five"),
 (6, "Six"), (7, "Seven"), (8, "Eight"), (9, "Nine");
-SET @save_dbug=@@debug_dbug;
+SET @saved_dbug=@@debug_dbug;
 SET SESSION debug_dbug="+d,ha_partition_fail_index_init";
 SELECT * FROM t1 WHERE b = "Seven";
 ERROR HY000: Table has no partition for value 0
-SET SESSION debug_dbug=@save_dbug;
+SET SESSION debug_dbug=@saved_dbug;
 SELECT * FROM t1 WHERE b = "Seven";
 a	b
 7	Seven
diff --git a/mysql-test/suite/parts/t/partition_debug.test b/mysql-test/suite/parts/t/partition_debug.test
index ef12ee99948..864452f8d8b 100644
--- a/mysql-test/suite/parts/t/partition_debug.test
+++ b/mysql-test/suite/parts/t/partition_debug.test
@@ -18,11 +18,11 @@ CREATE TABLE t1 (a INT, b VARCHAR(64), KEY(b,a))
   PARTITION BY HASH (a) PARTITIONS 3;
   INSERT INTO t1 VALUES (1, "1"), (2, "2"), (3, "3"), (4, "Four"), (5, "Five"),
   (6, "Six"), (7, "Seven"), (8, "Eight"), (9, "Nine");
-SET @save_dbug=@@debug_dbug;
+SET @saved_dbug=@@debug_dbug;
 SET SESSION debug_dbug="+d,ha_partition_fail_index_init";
 --error ER_NO_PARTITION_FOR_GIVEN_VALUE
 SELECT * FROM t1 WHERE b = "Seven";
-SET SESSION debug_dbug=@save_dbug;
+SET SESSION debug_dbug=@saved_dbug;
 SELECT * FROM t1 WHERE b = "Seven";
 DROP TABLE t1;
 
diff --git a/mysql-test/suite/parts/t/partition_debug_innodb.test b/mysql-test/suite/parts/t/partition_debug_innodb.test
index c3fa85ba5ba..0d065d0e3f2 100644
--- a/mysql-test/suite/parts/t/partition_debug_innodb.test
+++ b/mysql-test/suite/parts/t/partition_debug_innodb.test
@@ -30,7 +30,7 @@ INSERT INTO t1 VALUES (6, 'X 6 row'), (7, 'Seventh row'), (8, 'Last row');
 ALTER TABLE t1 ADD INDEX new_b_index (b);
 ALTER TABLE t1 DROP INDEX new_b_index;
 
-SET @save_dbug=@@debug_dbug;
+SET @saved_dbug=@@debug_dbug;
 SET SESSION debug_dbug = "+d,ha_partition_fail_final_add_index";
 
 --error ER_NO_PARTITION_FOR_GIVEN_VALUE
@@ -46,7 +46,7 @@ SHOW CREATE TABLE t1;
 --sorted_result
 SELECT * FROM t1;
 
-SET SESSION debug_dbug = @save_dbug;
+SET SESSION debug_dbug = @saved_dbug;
 SHOW CREATE TABLE t1;
 DROP TABLE t1;
 }
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_again_allow.result b/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_again_allow.result
index 27243b52422..86cab03c4c6 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_again_allow.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_again_allow.result
@@ -22,6 +22,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_error_again";
 connect  con2,"127.0.0.1",root,,test,$MASTER_MYPORT,;
 select "Con2 is alive";
@@ -99,4 +100,4 @@ FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
 revoke select on test.* from 'root'@'192.0.2.4';
 drop user 'root'@'192.0.2.4';
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_again_deny.result b/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_again_deny.result
index 7879919b09d..f824c319afa 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_again_deny.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_again_deny.result
@@ -20,6 +20,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_error_again";
 ERROR HY000: Host '192.0.2.4' is not allowed to connect to this MariaDB server
 connection default;
@@ -81,4 +82,4 @@ COUNT_LOCAL_ERRORS	0
 COUNT_UNKNOWN_ERRORS	0
 FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_bad_allow.result b/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_bad_allow.result
index 1d5923483c9..33948013822 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_bad_allow.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_bad_allow.result
@@ -22,6 +22,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_fake_bad_ipv4";
 connect  con2,"127.0.0.1",root,,test,$MASTER_MYPORT,;
 select "Con2 is alive";
@@ -99,4 +100,4 @@ FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
 revoke select on test.* from 'root'@'192.0.2.4';
 drop user 'root'@'192.0.2.4';
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_bad_deny.result b/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_bad_deny.result
index 87fc75817df..096c5c3dbd5 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_bad_deny.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_bad_deny.result
@@ -20,6 +20,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_fake_bad_ipv4";
 ERROR HY000: Host '192.0.2.4' is not allowed to connect to this MariaDB server
 connection default;
@@ -81,4 +82,4 @@ COUNT_LOCAL_ERRORS	0
 COUNT_UNKNOWN_ERRORS	0
 FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_good_allow.result b/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_good_allow.result
index 949fa8f9c3e..f36e4604a7c 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_good_allow.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_good_allow.result
@@ -22,6 +22,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_fake_good_ipv4";
 connect  con2,"127.0.0.1",root,,test,$MASTER_MYPORT,;
 select "Con2 is alive";
@@ -99,4 +100,4 @@ FIRST_ERROR_SEEN	null
 LAST_ERROR_SEEN	null
 revoke select on test.* from 'root'@'santa.claus.ipv4.example.com';
 drop user 'root'@'santa.claus.ipv4.example.com';
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_good_deny.result b/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_good_deny.result
index b2e0fb60811..d84ffe2e9df 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_good_deny.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_good_deny.result
@@ -20,6 +20,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_fake_good_ipv4";
 ERROR HY000: Host 'santa.claus.ipv4.example.com' is not allowed to connect to this MariaDB server
 connection default;
@@ -81,4 +82,4 @@ COUNT_LOCAL_ERRORS	0
 COUNT_UNKNOWN_ERRORS	0
 FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_noname_allow.result b/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_noname_allow.result
index bfc7fde5be8..ff2a93efec4 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_noname_allow.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_noname_allow.result
@@ -24,6 +24,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_error_noname";
 connect  con2,"127.0.0.1",root,,test,$MASTER_MYPORT,;
 select "Con2 is alive";
@@ -103,4 +104,4 @@ revoke select on test.* from 'root'@'santa.claus.ipv4.example.com';
 revoke select on test.* from 'root'@'192.0.2.4';
 drop user 'root'@'santa.claus.ipv4.example.com';
 drop user 'root'@'192.0.2.4';
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_noname_deny.result b/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_noname_deny.result
index 41eb9636e31..c300d6a50af 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_noname_deny.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_noname_deny.result
@@ -20,6 +20,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_error_noname";
 ERROR HY000: Host '192.0.2.4' is not allowed to connect to this MariaDB server
 connection default;
@@ -81,4 +82,4 @@ COUNT_LOCAL_ERRORS	0
 COUNT_UNKNOWN_ERRORS	0
 FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv4_auth_plugin.result b/mysql-test/suite/perfschema/r/hostcache_ipv4_auth_plugin.result
index 22dd7e7632c..1c34faa9457 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv4_auth_plugin.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv4_auth_plugin.result
@@ -24,6 +24,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_fake_good_ipv4";
 uninstall plugin test_plugin_server;
 ERROR HY000: Plugin 'test_plugin_server' is not loaded
@@ -194,5 +195,5 @@ REVOKE PROXY ON 'plug_dest'@'santa.claus.ipv4.example.com'
   FROM 'plug'@'santa.claus.ipv4.example.com';
 DROP USER 'plug'@'santa.claus.ipv4.example.com';
 DROP USER 'plug_dest'@'santa.claus.ipv4.example.com';
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 delete from mysql.plugin where name='test_plugin_server';
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv4_blocked.result b/mysql-test/suite/perfschema/r/hostcache_ipv4_blocked.result
index f301df94ce6..2751dbd7edb 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv4_blocked.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv4_blocked.result
@@ -25,6 +25,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_fake_good_ipv4,native_password_bad_reply";
 ERROR 08S01: Bad handshake
 connection default;
@@ -427,4 +428,4 @@ drop user 'root'@'santa.claus.ipv4.example.com';
 revoke select on test.* from 'quota'@'santa.claus.ipv4.example.com';
 drop user 'quota'@'santa.claus.ipv4.example.com';
 set global max_connect_errors = @saved_max_connect_errors;
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv4_format.result b/mysql-test/suite/perfschema/r/hostcache_ipv4_format.result
index 14a6ace09e4..18e437559e4 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv4_format.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv4_format.result
@@ -20,6 +20,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_format_ipv4";
 ERROR HY000: Host '192.0.2.4' is not allowed to connect to this MariaDB server
 connection default;
@@ -81,4 +82,4 @@ COUNT_LOCAL_ERRORS	0
 COUNT_UNKNOWN_ERRORS	0
 FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv4_max_con.result b/mysql-test/suite/perfschema/r/hostcache_ipv4_max_con.result
index 6cca75f9775..3d41f013ba9 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv4_max_con.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv4_max_con.result
@@ -25,6 +25,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_fake_good_ipv4";
 connect  con2a,"127.0.0.1",quota,,test,$MASTER_MYPORT,;
 select "Con2a is alive";
@@ -702,4 +703,4 @@ disconnect tmp_con7;
 set global max_connections = @saved_max_connections;
 set global max_user_connections = @saved_max_user_connections;
 drop user 'quota'@'santa.claus.ipv4.example.com';
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv4_nameinfo_again_allow.result b/mysql-test/suite/perfschema/r/hostcache_ipv4_nameinfo_again_allow.result
index 5aa80d90d84..7bafd9e636f 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv4_nameinfo_again_allow.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv4_nameinfo_again_allow.result
@@ -24,6 +24,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_error_again";
 connect  con2,"127.0.0.1",root,,test,$MASTER_MYPORT,;
 select "Con2 is alive";
@@ -178,4 +179,4 @@ revoke select on test.* from 'root'@'192.0.2.4';
 revoke select on test.* from 'root'@'santa.claus.ipv4.example.com';
 drop user 'root'@'192.0.2.4';
 drop user 'root'@'santa.claus.ipv4.example.com';
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv4_nameinfo_again_deny.result b/mysql-test/suite/perfschema/r/hostcache_ipv4_nameinfo_again_deny.result
index abe9a606bc4..3896ed086ba 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv4_nameinfo_again_deny.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv4_nameinfo_again_deny.result
@@ -20,6 +20,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_error_again";
 ERROR HY000: Host '192.0.2.4' is not allowed to connect to this MariaDB server
 connection default;
@@ -142,4 +143,4 @@ COUNT_LOCAL_ERRORS	0
 COUNT_UNKNOWN_ERRORS	0
 FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv4_nameinfo_noname_allow.result b/mysql-test/suite/perfschema/r/hostcache_ipv4_nameinfo_noname_allow.result
index 18986674491..236bc12d9bf 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv4_nameinfo_noname_allow.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv4_nameinfo_noname_allow.result
@@ -22,6 +22,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_error_noname";
 connect  con2,"127.0.0.1",root,,test,$MASTER_MYPORT,;
 select "Con2 is alive";
@@ -99,4 +100,4 @@ FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
 revoke select on test.* from 'root'@'192.0.2.4';
 drop user 'root'@'192.0.2.4';
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv4_nameinfo_noname_deny.result b/mysql-test/suite/perfschema/r/hostcache_ipv4_nameinfo_noname_deny.result
index 88ac817ce17..5479393c29b 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv4_nameinfo_noname_deny.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv4_nameinfo_noname_deny.result
@@ -20,6 +20,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_error_noname";
 ERROR HY000: Host '192.0.2.4' is not allowed to connect to this MariaDB server
 connection default;
@@ -81,4 +82,4 @@ COUNT_LOCAL_ERRORS	0
 COUNT_UNKNOWN_ERRORS	0
 FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv4_passwd.result b/mysql-test/suite/perfschema/r/hostcache_ipv4_passwd.result
index a5f70873ed9..4c2a9d48a63 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv4_passwd.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv4_passwd.result
@@ -24,6 +24,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_fake_good_ipv4";
 ERROR 28000: Access denied for user 'user_without'@'santa.claus.ipv4.example.com' (using password: YES)
 connection default;
@@ -207,4 +208,4 @@ FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
 drop user 'user_with'@'santa.claus.ipv4.example.com';
 drop user 'user_without'@'santa.claus.ipv4.example.com';
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv4_ssl.result b/mysql-test/suite/perfschema/r/hostcache_ipv4_ssl.result
index 86e7bf5780b..267f346836d 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv4_ssl.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv4_ssl.result
@@ -28,6 +28,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_fake_good_ipv4";
 ERROR 28000: Access denied for user 'user_ssl'@'santa.claus.ipv4.example.com' (using password: NO)
 connection default;
@@ -151,4 +152,4 @@ FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
 drop user 'user_ssl'@'santa.claus.ipv4.example.com';
 drop user 'user_ssl_x509'@'santa.claus.ipv4.example.com';
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_again_allow.result b/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_again_allow.result
index 42d86e858fb..4325cfec6dc 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_again_allow.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_again_allow.result
@@ -22,6 +22,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_error_again";
 connect  con2,"::1",root,,test,$MASTER_MYPORT,;
 select "Con2 is alive";
@@ -99,4 +100,4 @@ FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
 revoke select on test.* from 'root'@'2001:db8::6:6';
 drop user 'root'@'2001:db8::6:6';
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_again_deny.result b/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_again_deny.result
index 87e97ba2138..12435dd54f5 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_again_deny.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_again_deny.result
@@ -20,6 +20,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_error_again";
 ERROR HY000: Host '2001:db8::6:6' is not allowed to connect to this MariaDB server
 connection default;
@@ -81,4 +82,4 @@ COUNT_LOCAL_ERRORS	0
 COUNT_UNKNOWN_ERRORS	0
 FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_bad_allow.result b/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_bad_allow.result
index bcd47243d03..57e14dfe913 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_bad_allow.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_bad_allow.result
@@ -22,6 +22,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_fake_bad_ipv6";
 connect  con2,"::1",root,,test,$MASTER_MYPORT,;
 select "Con2 is alive";
@@ -99,4 +100,4 @@ FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
 revoke select on test.* from 'root'@'2001:db8::6:6';
 drop user 'root'@'2001:db8::6:6';
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_bad_deny.result b/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_bad_deny.result
index 5c24a86248a..654ed7759b1 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_bad_deny.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_bad_deny.result
@@ -20,6 +20,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_fake_bad_ipv6";
 ERROR HY000: Host '2001:db8::6:6' is not allowed to connect to this MariaDB server
 connection default;
@@ -81,4 +82,4 @@ COUNT_LOCAL_ERRORS	0
 COUNT_UNKNOWN_ERRORS	0
 FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_good_allow.result b/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_good_allow.result
index 68ea9a1d826..f68d90978e7 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_good_allow.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_good_allow.result
@@ -22,6 +22,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_fake_good_ipv6";
 connect  con2,"::1",root,,test,$MASTER_MYPORT,;
 select "Con2 is alive";
@@ -99,4 +100,4 @@ FIRST_ERROR_SEEN	null
 LAST_ERROR_SEEN	null
 revoke select on test.* from 'root'@'santa.claus.ipv6.example.com';
 drop user 'root'@'santa.claus.ipv6.example.com';
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_good_deny.result b/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_good_deny.result
index 5b1f546b30e..e63c84bf352 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_good_deny.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_good_deny.result
@@ -19,6 +19,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_fake_good_ipv6";
 ERROR HY000: Host 'santa.claus.ipv6.example.com' is not allowed to connect to this MariaDB server
 connection default;
@@ -80,4 +81,4 @@ COUNT_LOCAL_ERRORS	0
 COUNT_UNKNOWN_ERRORS	0
 FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_noname_allow.result b/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_noname_allow.result
index 0a3a3329c1e..50297797f6a 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_noname_allow.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_noname_allow.result
@@ -24,6 +24,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_error_noname";
 connect  con2,"::1",root,,test,$MASTER_MYPORT,;
 select "Con2 is alive";
@@ -103,4 +104,4 @@ revoke select on test.* from 'root'@'santa.claus.ipv6.example.com';
 revoke select on test.* from 'root'@'2001:db8::6:6';
 drop user 'root'@'santa.claus.ipv6.example.com';
 drop user 'root'@'2001:db8::6:6';
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_noname_deny.result b/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_noname_deny.result
index 493ada909b7..549e83369df 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_noname_deny.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_noname_deny.result
@@ -20,6 +20,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_error_noname";
 ERROR HY000: Host '2001:db8::6:6' is not allowed to connect to this MariaDB server
 connection default;
@@ -81,4 +82,4 @@ COUNT_LOCAL_ERRORS	0
 COUNT_UNKNOWN_ERRORS	0
 FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv6_auth_plugin.result b/mysql-test/suite/perfschema/r/hostcache_ipv6_auth_plugin.result
index a36d1442ee6..5312958bd91 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv6_auth_plugin.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv6_auth_plugin.result
@@ -24,6 +24,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_fake_good_ipv6";
 uninstall plugin test_plugin_server;
 ERROR HY000: Plugin 'test_plugin_server' is not loaded
@@ -194,5 +195,5 @@ REVOKE PROXY ON 'plug_dest'@'santa.claus.ipv6.example.com'
   FROM 'plug'@'santa.claus.ipv6.example.com';
 DROP USER 'plug'@'santa.claus.ipv6.example.com';
 DROP USER 'plug_dest'@'santa.claus.ipv6.example.com';
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 delete from mysql.plugin where name='test_plugin_server';
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv6_blocked.result b/mysql-test/suite/perfschema/r/hostcache_ipv6_blocked.result
index 7cfb6f87277..757285b1033 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv6_blocked.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv6_blocked.result
@@ -25,6 +25,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_fake_good_ipv6,native_password_bad_reply";
 ERROR 08S01: Bad handshake
 connection default;
@@ -427,4 +428,4 @@ drop user 'root'@'santa.claus.ipv6.example.com';
 revoke select on test.* from 'quota'@'santa.claus.ipv6.example.com';
 drop user 'quota'@'santa.claus.ipv6.example.com';
 set global max_connect_errors = @saved_max_connect_errors;
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv6_max_con.result b/mysql-test/suite/perfschema/r/hostcache_ipv6_max_con.result
index f9d2b556804..f2e25ab6ca1 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv6_max_con.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv6_max_con.result
@@ -25,6 +25,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_fake_good_ipv6";
 connect  con2a,"::1",quota,,test,$MASTER_MYPORT,;
 select "Con2a is alive";
@@ -702,4 +703,4 @@ disconnect tmp_con7;
 set global max_connections = @saved_max_connections;
 set global max_user_connections = @saved_max_user_connections;
 drop user 'quota'@'santa.claus.ipv6.example.com';
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv6_nameinfo_again_allow.result b/mysql-test/suite/perfschema/r/hostcache_ipv6_nameinfo_again_allow.result
index 6140f655e7c..2bb23e99203 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv6_nameinfo_again_allow.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv6_nameinfo_again_allow.result
@@ -24,6 +24,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_error_again";
 connect  con2,"::1",root,,test,$MASTER_MYPORT,;
 select "Con2 is alive";
@@ -178,4 +179,4 @@ revoke select on test.* from 'root'@'2001:db8::6:6';
 revoke select on test.* from 'root'@'santa.claus.ipv6.example.com';
 drop user 'root'@'2001:db8::6:6';
 drop user 'root'@'santa.claus.ipv6.example.com';
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv6_nameinfo_again_deny.result b/mysql-test/suite/perfschema/r/hostcache_ipv6_nameinfo_again_deny.result
index 22ce0c3e809..5befbd98087 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv6_nameinfo_again_deny.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv6_nameinfo_again_deny.result
@@ -20,6 +20,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_error_again";
 ERROR HY000: Host '2001:db8::6:6' is not allowed to connect to this MariaDB server
 connection default;
@@ -142,4 +143,4 @@ COUNT_LOCAL_ERRORS	0
 COUNT_UNKNOWN_ERRORS	0
 FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv6_nameinfo_noname_allow.result b/mysql-test/suite/perfschema/r/hostcache_ipv6_nameinfo_noname_allow.result
index a78ba09513c..f899cb935e9 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv6_nameinfo_noname_allow.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv6_nameinfo_noname_allow.result
@@ -22,6 +22,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_error_noname";
 connect  con2,"::1",root,,test,$MASTER_MYPORT,;
 select "Con2 is alive";
@@ -99,4 +100,4 @@ FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
 revoke select on test.* from 'root'@'2001:db8::6:6';
 drop user 'root'@'2001:db8::6:6';
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv6_nameinfo_noname_deny.result b/mysql-test/suite/perfschema/r/hostcache_ipv6_nameinfo_noname_deny.result
index da1570f1b37..6d50530ffa0 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv6_nameinfo_noname_deny.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv6_nameinfo_noname_deny.result
@@ -20,6 +20,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_error_noname";
 ERROR HY000: Host '2001:db8::6:6' is not allowed to connect to this MariaDB server
 connection default;
@@ -81,4 +82,4 @@ COUNT_LOCAL_ERRORS	0
 COUNT_UNKNOWN_ERRORS	0
 FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv6_passwd.result b/mysql-test/suite/perfschema/r/hostcache_ipv6_passwd.result
index a4cc3eeb0d0..670a3713d91 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv6_passwd.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv6_passwd.result
@@ -24,6 +24,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_fake_good_ipv6";
 ERROR 28000: Access denied for user 'user_without'@'santa.claus.ipv6.example.com' (using password: YES)
 connection default;
@@ -207,4 +208,4 @@ FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
 drop user 'user_with'@'santa.claus.ipv6.example.com';
 drop user 'user_without'@'santa.claus.ipv6.example.com';
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv6_ssl.result b/mysql-test/suite/perfschema/r/hostcache_ipv6_ssl.result
index 75f8e5391cf..9ec33df2fee 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv6_ssl.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv6_ssl.result
@@ -28,6 +28,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_fake_good_ipv6";
 ERROR 28000: Access denied for user 'user_ssl'@'santa.claus.ipv6.example.com' (using password: NO)
 connection default;
@@ -151,4 +152,4 @@ FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
 drop user 'user_ssl'@'santa.claus.ipv6.example.com';
 drop user 'user_ssl_x509'@'santa.claus.ipv6.example.com';
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_peer_addr.result b/mysql-test/suite/perfschema/r/hostcache_peer_addr.result
index ddb44157f44..6d15f2f5b25 100644
--- a/mysql-test/suite/perfschema/r/hostcache_peer_addr.result
+++ b/mysql-test/suite/perfschema/r/hostcache_peer_addr.result
@@ -27,6 +27,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_error";
 ERROR HY000: Can't get hostname for your address
 connection default;
@@ -50,7 +51,7 @@ Connection_errors_peer_address	2
 Connection_errors_select	0
 Connection_errors_tcpwrap	0
 "Dumping performance_schema.host_cache"
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 flush status;
 show global status like "connection_errors_%";
 Variable_name	Value
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_again_allow.test b/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_again_allow.test
index 6bed01e50bf..c96c8ea37c8 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_again_allow.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_again_allow.test
@@ -27,6 +27,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_error_again";
 
 connect (con2,"127.0.0.1",root,,test,$MASTER_MYPORT,);
@@ -48,5 +49,5 @@ disconnect con3;
 revoke select on test.* from 'root'@'192.0.2.4';
 drop user 'root'@'192.0.2.4';
 
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_again_deny.test b/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_again_deny.test
index 3c72de8a05e..00f5d218e17 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_again_deny.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_again_deny.test
@@ -25,6 +25,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_error_again";
 
 --disable_query_log
@@ -43,5 +44,5 @@ connect (con3,"127.0.0.1",root,,test,$MASTER_MYPORT,);
 --connection default
 --source ../include/hostcache_dump.inc
 
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_bad_allow.test b/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_bad_allow.test
index 5cbe4c30530..d2dff92834e 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_bad_allow.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_bad_allow.test
@@ -30,6 +30,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_fake_bad_ipv4";
 
 connect (con2,"127.0.0.1",root,,test,$MASTER_MYPORT,);
@@ -51,5 +52,5 @@ disconnect con3;
 revoke select on test.* from 'root'@'192.0.2.4';
 drop user 'root'@'192.0.2.4';
 
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_bad_deny.test b/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_bad_deny.test
index c0639cd6b86..f37e1ed3b90 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_bad_deny.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_bad_deny.test
@@ -27,6 +27,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_fake_bad_ipv4";
 
 --disable_query_log
@@ -45,5 +46,5 @@ connect (con3,"127.0.0.1",root,,test,$MASTER_MYPORT,);
 --connection default
 --source ../include/hostcache_dump.inc
 
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_good_allow.test b/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_good_allow.test
index 3b69e0731a0..d2b5352d3a6 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_good_allow.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_good_allow.test
@@ -28,6 +28,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_fake_good_ipv4";
 
 connect (con2,"127.0.0.1",root,,test,$MASTER_MYPORT,);
@@ -49,5 +50,5 @@ disconnect con3;
 revoke select on test.* from 'root'@'santa.claus.ipv4.example.com';
 drop user 'root'@'santa.claus.ipv4.example.com';
 
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_good_deny.test b/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_good_deny.test
index e6478c13951..55afb6f0c4f 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_good_deny.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_good_deny.test
@@ -25,6 +25,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_fake_good_ipv4";
 
 --disable_query_log
@@ -43,5 +44,5 @@ connect (con3,"127.0.0.1",root,,test,$MASTER_MYPORT,);
 --connection default
 --source ../include/hostcache_dump.inc
 
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_noname_allow.test b/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_noname_allow.test
index b4b11526af6..a6bd4c751e2 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_noname_allow.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_noname_allow.test
@@ -30,6 +30,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_error_noname";
 
 connect (con2,"127.0.0.1",root,,test,$MASTER_MYPORT,);
@@ -53,5 +54,5 @@ revoke select on test.* from 'root'@'192.0.2.4';
 drop user 'root'@'santa.claus.ipv4.example.com';
 drop user 'root'@'192.0.2.4';
 
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_noname_deny.test b/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_noname_deny.test
index 06f0f7d29ee..41b8b25efc4 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_noname_deny.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_noname_deny.test
@@ -25,6 +25,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_error_noname";
 
 --disable_query_log
@@ -43,5 +44,5 @@ connect (con3,"127.0.0.1",root,,test,$MASTER_MYPORT,);
 --connection default
 --source ../include/hostcache_dump.inc
 
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv4_auth_plugin.test b/mysql-test/suite/perfschema/t/hostcache_ipv4_auth_plugin.test
index 325460e66ba..6e149b838ef 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv4_auth_plugin.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv4_auth_plugin.test
@@ -30,6 +30,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_fake_good_ipv4";
 uninstall plugin test_plugin_server;
 
@@ -86,6 +87,6 @@ REVOKE PROXY ON 'plug_dest'@'santa.claus.ipv4.example.com'
 DROP USER 'plug'@'santa.claus.ipv4.example.com';
 DROP USER 'plug_dest'@'santa.claus.ipv4.example.com';
 
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 delete from mysql.plugin where name='test_plugin_server';
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv4_blocked.test b/mysql-test/suite/perfschema/t/hostcache_ipv4_blocked.test
index 6990a4e7118..d304cc5a1b8 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv4_blocked.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv4_blocked.test
@@ -33,6 +33,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_fake_good_ipv4,native_password_bad_reply";
 
 --disable_query_log
@@ -156,5 +157,5 @@ revoke select on test.* from 'quota'@'santa.claus.ipv4.example.com';
 drop user 'quota'@'santa.claus.ipv4.example.com';
 
 set global max_connect_errors = @saved_max_connect_errors;
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv4_format.test b/mysql-test/suite/perfschema/t/hostcache_ipv4_format.test
index b37bfc79ada..989c82ef0ad 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv4_format.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv4_format.test
@@ -24,6 +24,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_format_ipv4";
 
 --disable_query_log
@@ -42,5 +43,5 @@ connect (con3,"127.0.0.1",root,,test,$MASTER_MYPORT,);
 --connection default
 --source ../include/hostcache_dump.inc
 
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv4_max_con.test b/mysql-test/suite/perfschema/t/hostcache_ipv4_max_con.test
index c0349184506..6420b8b5300 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv4_max_con.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv4_max_con.test
@@ -31,6 +31,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_fake_good_ipv4";
 
 connect (con2a,"127.0.0.1",quota,,test,$MASTER_MYPORT,);
@@ -259,5 +260,5 @@ set global max_user_connections = @saved_max_user_connections;
 # revoke all privileges on test.* from 'quota'@'santa.claus.ipv4.example.com';
 drop user 'quota'@'santa.claus.ipv4.example.com';
 
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv4_nameinfo_again_allow.test b/mysql-test/suite/perfschema/t/hostcache_ipv4_nameinfo_again_allow.test
index 187879985c9..5a2caf5849e 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv4_nameinfo_again_allow.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv4_nameinfo_again_allow.test
@@ -30,6 +30,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_error_again";
 
 connect (con2,"127.0.0.1",root,,test,$MASTER_MYPORT,);
@@ -71,5 +72,5 @@ revoke select on test.* from 'root'@'santa.claus.ipv4.example.com';
 drop user 'root'@'192.0.2.4';
 drop user 'root'@'santa.claus.ipv4.example.com';
 
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv4_nameinfo_again_deny.test b/mysql-test/suite/perfschema/t/hostcache_ipv4_nameinfo_again_deny.test
index a78c0dab4eb..6cd2664a04f 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv4_nameinfo_again_deny.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv4_nameinfo_again_deny.test
@@ -25,6 +25,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_error_again";
 
 --disable_query_log
@@ -61,5 +62,5 @@ connect (con5,"127.0.0.1",root,,test,$MASTER_MYPORT,);
 --connection default
 --source ../include/hostcache_dump.inc
 
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv4_nameinfo_noname_allow.test b/mysql-test/suite/perfschema/t/hostcache_ipv4_nameinfo_noname_allow.test
index 23ecd51eb4f..19a3ebe9892 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv4_nameinfo_noname_allow.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv4_nameinfo_noname_allow.test
@@ -28,6 +28,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_error_noname";
 
 connect (con2,"127.0.0.1",root,,test,$MASTER_MYPORT,);
@@ -49,5 +50,5 @@ disconnect con3;
 revoke select on test.* from 'root'@'192.0.2.4';
 drop user 'root'@'192.0.2.4';
 
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv4_nameinfo_noname_deny.test b/mysql-test/suite/perfschema/t/hostcache_ipv4_nameinfo_noname_deny.test
index 4b6c91c3df3..28e5615d273 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv4_nameinfo_noname_deny.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv4_nameinfo_noname_deny.test
@@ -25,6 +25,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_error_noname";
 
 --disable_query_log
@@ -43,5 +44,5 @@ connect (con3,"127.0.0.1",root,,test,$MASTER_MYPORT,);
 --connection default
 --source ../include/hostcache_dump.inc
 
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv4_passwd.test b/mysql-test/suite/perfschema/t/hostcache_ipv4_passwd.test
index ea331647b48..c6ff89f0902 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv4_passwd.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv4_passwd.test
@@ -29,6 +29,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_fake_good_ipv4";
 
 --disable_query_log
@@ -82,5 +83,5 @@ connect (con2f,"127.0.0.1",user_with,wrong_password,test,$MASTER_MYPORT,);
 drop user 'user_with'@'santa.claus.ipv4.example.com';
 drop user 'user_without'@'santa.claus.ipv4.example.com';
 
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv4_ssl.test b/mysql-test/suite/perfschema/t/hostcache_ipv4_ssl.test
index 2b949098bad..bd8d48984e4 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv4_ssl.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv4_ssl.test
@@ -30,6 +30,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_fake_good_ipv4";
 
 --disable_query_log
@@ -67,5 +68,5 @@ connect (con2d,"127.0.0.1",user_ssl_x509,good_password,test,$MASTER_MYPORT,,SSL)
 drop user 'user_ssl'@'santa.claus.ipv4.example.com';
 drop user 'user_ssl_x509'@'santa.claus.ipv4.example.com';
 
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_again_allow.test b/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_again_allow.test
index 11c45724f70..100fdffa377 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_again_allow.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_again_allow.test
@@ -29,6 +29,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_error_again";
 
 connect (con2,"::1",root,,test,$MASTER_MYPORT,);
@@ -50,5 +51,5 @@ disconnect con3;
 revoke select on test.* from 'root'@'2001:db8::6:6';
 drop user 'root'@'2001:db8::6:6';
 
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_again_deny.test b/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_again_deny.test
index bdbc0e3c025..8aafff745c4 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_again_deny.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_again_deny.test
@@ -26,6 +26,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_error_again";
 
 --disable_query_log
@@ -44,5 +45,5 @@ connect (con3,"::1",root,,test,$MASTER_MYPORT,);
 --connection default
 --source ../include/hostcache_dump.inc
 
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_bad_allow.test b/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_bad_allow.test
index 1eb0d3ec41f..eaf46a5c57e 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_bad_allow.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_bad_allow.test
@@ -31,6 +31,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_fake_bad_ipv6";
 
 connect (con2,"::1",root,,test,$MASTER_MYPORT,);
@@ -52,5 +53,5 @@ disconnect con3;
 revoke select on test.* from 'root'@'2001:db8::6:6';
 drop user 'root'@'2001:db8::6:6';
 
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_bad_deny.test b/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_bad_deny.test
index f8a3cc23c00..6c4ede9da8e 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_bad_deny.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_bad_deny.test
@@ -28,6 +28,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_fake_bad_ipv6";
 
 --disable_query_log
@@ -46,5 +47,5 @@ connect (con3,"::1",root,,test,$MASTER_MYPORT,);
 --connection default
 --source ../include/hostcache_dump.inc
 
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_good_allow.test b/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_good_allow.test
index 6493bb61a1a..e290a5f8ab4 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_good_allow.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_good_allow.test
@@ -29,6 +29,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_fake_good_ipv6";
 
 connect (con2,"::1",root,,test,$MASTER_MYPORT,);
@@ -50,5 +51,5 @@ disconnect con3;
 revoke select on test.* from 'root'@'santa.claus.ipv6.example.com';
 drop user 'root'@'santa.claus.ipv6.example.com';
 
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_good_deny.test b/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_good_deny.test
index 065ae02dd49..4feb0ffb7c8 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_good_deny.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_good_deny.test
@@ -22,6 +22,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_fake_good_ipv6";
 
 --disable_query_log
@@ -40,5 +41,5 @@ connect (con3,"::1",root,,test,$MASTER_MYPORT,);
 --connection default
 --source ../include/hostcache_dump.inc
 
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_noname_allow.test b/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_noname_allow.test
index 9ebafc9627d..6b422a19dbd 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_noname_allow.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_noname_allow.test
@@ -31,6 +31,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_error_noname";
 
 connect (con2,"::1",root,,test,$MASTER_MYPORT,);
@@ -54,5 +55,4 @@ revoke select on test.* from 'root'@'2001:db8::6:6';
 drop user 'root'@'santa.claus.ipv6.example.com';
 drop user 'root'@'2001:db8::6:6';
 
-set global debug_dbug= default;
-
+SET @@GLOBAL.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_noname_deny.test b/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_noname_deny.test
index 136b3c7a24f..c81b799edd1 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_noname_deny.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_noname_deny.test
@@ -26,6 +26,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_error_noname";
 
 --disable_query_log
@@ -44,5 +45,4 @@ connect (con3,"::1",root,,test,$MASTER_MYPORT,);
 --connection default
 --source ../include/hostcache_dump.inc
 
-set global debug_dbug= default;
-
+SET @@GLOBAL.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv6_auth_plugin.test b/mysql-test/suite/perfschema/t/hostcache_ipv6_auth_plugin.test
index 3a822bfacb3..d2e4ed69d79 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv6_auth_plugin.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv6_auth_plugin.test
@@ -31,6 +31,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_fake_good_ipv6";
 uninstall plugin test_plugin_server;
 
@@ -87,6 +88,6 @@ REVOKE PROXY ON 'plug_dest'@'santa.claus.ipv6.example.com'
 DROP USER 'plug'@'santa.claus.ipv6.example.com';
 DROP USER 'plug_dest'@'santa.claus.ipv6.example.com';
 
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 delete from mysql.plugin where name='test_plugin_server';
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv6_blocked.test b/mysql-test/suite/perfschema/t/hostcache_ipv6_blocked.test
index 0a04ec306cf..6da99e02444 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv6_blocked.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv6_blocked.test
@@ -33,6 +33,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_fake_good_ipv6,native_password_bad_reply";
 
 --disable_query_log
@@ -156,5 +157,5 @@ revoke select on test.* from 'quota'@'santa.claus.ipv6.example.com';
 drop user 'quota'@'santa.claus.ipv6.example.com';
 
 set global max_connect_errors = @saved_max_connect_errors;
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv6_max_con.test b/mysql-test/suite/perfschema/t/hostcache_ipv6_max_con.test
index b14fff1cc72..6f83221c496 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv6_max_con.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv6_max_con.test
@@ -32,6 +32,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_fake_good_ipv6";
 
 connect (con2a,"::1",quota,,test,$MASTER_MYPORT,);
@@ -241,5 +242,5 @@ set global max_user_connections = @saved_max_user_connections;
 # revoke all privileges on test.* from 'quota'@'santa.claus.ipv6.example.com';
 drop user 'quota'@'santa.claus.ipv6.example.com';
 
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv6_nameinfo_again_allow.test b/mysql-test/suite/perfschema/t/hostcache_ipv6_nameinfo_again_allow.test
index b44b58eb0d5..896b9bb4886 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv6_nameinfo_again_allow.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv6_nameinfo_again_allow.test
@@ -31,6 +31,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_error_again";
 
 connect (con2,"::1",root,,test,$MASTER_MYPORT,);
@@ -72,5 +73,5 @@ revoke select on test.* from 'root'@'santa.claus.ipv6.example.com';
 drop user 'root'@'2001:db8::6:6';
 drop user 'root'@'santa.claus.ipv6.example.com';
 
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv6_nameinfo_again_deny.test b/mysql-test/suite/perfschema/t/hostcache_ipv6_nameinfo_again_deny.test
index 073451c7e75..17cc1ffa528 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv6_nameinfo_again_deny.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv6_nameinfo_again_deny.test
@@ -26,6 +26,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_error_again";
 
 --disable_query_log
@@ -62,5 +63,5 @@ connect (con5,"::1",root,,test,$MASTER_MYPORT,);
 --connection default
 --source ../include/hostcache_dump.inc
 
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv6_nameinfo_noname_allow.test b/mysql-test/suite/perfschema/t/hostcache_ipv6_nameinfo_noname_allow.test
index a7b1a961f09..8e31420b6f1 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv6_nameinfo_noname_allow.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv6_nameinfo_noname_allow.test
@@ -29,6 +29,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_error_noname";
 
 connect (con2,"::1",root,,test,$MASTER_MYPORT,);
@@ -50,5 +51,5 @@ disconnect con3;
 revoke select on test.* from 'root'@'2001:db8::6:6';
 drop user 'root'@'2001:db8::6:6';
 
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv6_nameinfo_noname_deny.test b/mysql-test/suite/perfschema/t/hostcache_ipv6_nameinfo_noname_deny.test
index 5c3d643b166..ddffc820a2b 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv6_nameinfo_noname_deny.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv6_nameinfo_noname_deny.test
@@ -26,6 +26,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_error_noname";
 
 --disable_query_log
@@ -44,5 +45,5 @@ connect (con3,"::1",root,,test,$MASTER_MYPORT,);
 --connection default
 --source ../include/hostcache_dump.inc
 
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv6_passwd.test b/mysql-test/suite/perfschema/t/hostcache_ipv6_passwd.test
index 7dcfbb922e5..7281a8b36ec 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv6_passwd.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv6_passwd.test
@@ -27,6 +27,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_fake_good_ipv6";
 
 --disable_query_log
@@ -80,5 +81,5 @@ connect (con2f,"::1",user_with,wrong_password,test,$MASTER_MYPORT,);
 drop user 'user_with'@'santa.claus.ipv6.example.com';
 drop user 'user_without'@'santa.claus.ipv6.example.com';
 
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv6_ssl.test b/mysql-test/suite/perfschema/t/hostcache_ipv6_ssl.test
index 3ea4451c7aa..d822d9f9bed 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv6_ssl.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv6_ssl.test
@@ -31,6 +31,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_fake_good_ipv6";
 
 --disable_query_log
@@ -68,5 +69,5 @@ connect (con2d,"::1",user_ssl_x509,good_password,test,$MASTER_MYPORT,,SSL);
 drop user 'user_ssl'@'santa.claus.ipv6.example.com';
 drop user 'user_ssl_x509'@'santa.claus.ipv6.example.com';
 
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_peer_addr.test b/mysql-test/suite/perfschema/t/hostcache_peer_addr.test
index 65f33ce73a8..827421312dc 100644
--- a/mysql-test/suite/perfschema/t/hostcache_peer_addr.test
+++ b/mysql-test/suite/perfschema/t/hostcache_peer_addr.test
@@ -22,6 +22,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_error";
 
 --disable_query_log
@@ -42,7 +43,7 @@ connect (con3,"127.0.0.1",root,,test,$MASTER_MYPORT,);
 show global status like "connection_errors_%";
 --source ../include/hostcache_dump.inc
 
-set global debug_dbug= default;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 
 flush status;
 show global status like "connection_errors_%";
diff --git a/mysql-test/suite/rpl/include/rpl_checksum.inc b/mysql-test/suite/rpl/include/rpl_checksum.inc
index b5e70abe4d0..17a986dc308 100644
--- a/mysql-test/suite/rpl/include/rpl_checksum.inc
+++ b/mysql-test/suite/rpl/include/rpl_checksum.inc
@@ -108,6 +108,7 @@ insert into t1 values (1) /* will not be applied on slave due to simulation */;
 # instruction to the dump thread
 
 connection slave;
+set @saved_dbug = @@global.debug_dbug;
 set @@global.debug_dbug='d,simulate_slave_unaware_checksum';
 start slave;
 --let $slave_io_errno= 1236
@@ -116,8 +117,7 @@ source include/wait_for_slave_io_error.inc;
 
 select count(*) as zero from t1;
 
-###connection master;
-set @@global.debug_dbug='';
+set @@global.debug_dbug = @saved_dbug;
 
 connection slave;
 source include/start_slave.inc;
@@ -129,10 +129,11 @@ source include/start_slave.inc;
 # C1. Failure by a client thread
 connection master;
 set @@global.master_verify_checksum = 1;
+set @save_dbug = @@session.debug_dbug;
 set @@session.debug_dbug='d,simulate_checksum_test_failure';
 --error ER_ERROR_WHEN_EXECUTING_COMMAND
 show binlog events;
-set @@session.debug_dbug='';
+SET debug_dbug= @save_dbug;
 set @@global.master_verify_checksum = default;
 
 #connection master;
@@ -149,6 +150,7 @@ connection slave;
 
 # C2. Failure by IO thread
 # instruction to io thread
+set @saved_dbug = @@global.debug_dbug;
 set @@global.debug_dbug='d,simulate_checksum_test_failure';
 start slave io_thread;
 # When the checksum error is detected, the slave sets error code 1913
@@ -158,7 +160,7 @@ start slave io_thread;
 --let $slave_io_errno= 1595,1913
 --let $show_slave_io_error= 0
 source include/wait_for_slave_io_error.inc;
-set @@global.debug_dbug='';
+set @@global.debug_dbug = @saved_dbug;
 
 # to make IO thread re-read it again w/o the failure
 start slave io_thread;
@@ -179,7 +181,7 @@ source include/wait_for_slave_sql_error.inc;
 
 # resuming SQL thread to parse out the event w/o the failure
 
-set @@global.debug_dbug=''; 
+set @@global.debug_dbug = @saved_dbug;
 source include/start_slave.inc;
 
 connection master;
diff --git a/mysql-test/suite/rpl/include/rpl_corruption.inc b/mysql-test/suite/rpl/include/rpl_corruption.inc
index 1726ee4ba2f..88f683ed53d 100644
--- a/mysql-test/suite/rpl/include/rpl_corruption.inc
+++ b/mysql-test/suite/rpl/include/rpl_corruption.inc
@@ -73,6 +73,7 @@ while ($i) {
 
 # Emulate corruption in binlog file when SHOW BINLOG EVENTS is executing
 --echo # 2. Corruption in master binlog and SHOW BINLOG EVENTS
+set @saved_dbug = @@global.debug_dbug;
 SET GLOBAL debug_dbug="+d,corrupt_read_log_event_char";
 --echo SHOW BINLOG EVENTS;
 --disable_query_log
@@ -167,10 +168,10 @@ let $diff_tables= master:test.t1, slave:test.t1;
 # Clean up
 --echo # 8. Clean up
 --connection master
-SET GLOBAL debug_dbug= "";
+set @@global.debug_dbug = @saved_dbug;
 SET GLOBAL master_verify_checksum = @old_master_verify_checksum;
 DROP TABLE t1;
 --sync_slave_with_master
-SET GLOBAL debug_dbug= "";
+set @@global.debug_dbug = @saved_dbug;
 
 --source include/rpl_end.inc
diff --git a/mysql-test/suite/rpl/include/rpl_incident.inc b/mysql-test/suite/rpl/include/rpl_incident.inc
index 350a2086681..75d28d6a6c6 100644
--- a/mysql-test/suite/rpl/include/rpl_incident.inc
+++ b/mysql-test/suite/rpl/include/rpl_incident.inc
@@ -20,7 +20,7 @@ CREATE TABLE t1 (a INT);
 INSERT INTO t1 VALUES (1),(2),(3);
 SELECT * FROM t1;
 
-let $debug_save= `SELECT @@GLOBAL.debug`;
+set @saved_dbug = @@global.debug_dbug;
 SET GLOBAL debug_dbug= '+d,incident_database_resync_on_replace,*';
 
 # This will generate an incident log event and store it in the binary
@@ -29,9 +29,7 @@ REPLACE INTO t1 VALUES (4);
 --save_master_pos
 SELECT * FROM t1;
 
---disable_query_log
-eval SET GLOBAL debug_dbug= '$debug_save';
---enable_query_log
+set @@global.debug_dbug = @saved_dbug;
 
 connection slave;
 # Wait until SQL thread stops with error LOST_EVENT on master
diff --git a/mysql-test/suite/rpl/include/rpl_init_slave_errors.inc b/mysql-test/suite/rpl/include/rpl_init_slave_errors.inc
index 4fdea651edd..46673ea4764 100644
--- a/mysql-test/suite/rpl/include/rpl_init_slave_errors.inc
+++ b/mysql-test/suite/rpl/include/rpl_init_slave_errors.inc
@@ -51,6 +51,7 @@ reset slave;
 connection slave;
 
 # Set debug flags on slave to force errors to occur
+set @saved_dbug = @@global.debug_dbug;
 SET GLOBAL debug_dbug= "d,simulate_io_slave_error_on_init,simulate_sql_slave_error_on_init";
 
 start slave;
@@ -66,7 +67,7 @@ start slave;
 
 call mtr.add_suppression("Failed during slave.* thread initialization");
 
-SET GLOBAL debug_dbug= "";
+set @@global.debug_dbug = @saved_dbug;
 
 ######################################################################
 #             Injecting faults in the init_slave option
diff --git a/mysql-test/suite/rpl/r/kill_race_condition.result b/mysql-test/suite/rpl/r/kill_race_condition.result
index 1181eb0b0b1..8e8645cdb58 100644
--- a/mysql-test/suite/rpl/r/kill_race_condition.result
+++ b/mysql-test/suite/rpl/r/kill_race_condition.result
@@ -4,6 +4,7 @@ connection master;
 create table t1 (a int);
 connection slave;
 connection slave;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug='d,rows_log_event_before_open_table';
 connection master;
 insert t1 values (1),(2),(3);
@@ -13,7 +14,7 @@ kill slave_sql_thread;
 set debug_sync='now SIGNAL go_ahead_sql';
 include/wait_for_slave_sql_error.inc [errno=1927]
 Last_SQL_Error = Error executing row event: 'Connection was killed'
-set global debug_dbug='';
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 set debug_sync='RESET';
 connection master;
 drop table t1;
diff --git a/mysql-test/suite/rpl/r/rpl_binlog_rollback_cleanup.result b/mysql-test/suite/rpl/r/rpl_binlog_rollback_cleanup.result
new file mode 100644
index 00000000000..a677cbfecf6
--- /dev/null
+++ b/mysql-test/suite/rpl/r/rpl_binlog_rollback_cleanup.result
@@ -0,0 +1,9 @@
+include/master-slave.inc
+[connection master]
+connection master;
+SET GLOBAL max_binlog_cache_size = 65536;
+CREATE TABLE t1(a INT PRIMARY KEY, data VARCHAR(30000)) ENGINE=INNODB;
+ERROR HY000: Multi-statement transaction required more than 'max_binlog_cache_size' bytes of storage; increase this mysqld variable and try again
+SET GLOBAL max_binlog_cache_size= ORIGINAL_VALUE;
+DROP TABLE t1;
+include/rpl_end.inc
diff --git a/mysql-test/suite/rpl/r/rpl_bug33931.result b/mysql-test/suite/rpl/r/rpl_bug33931.result
index 74ba945b027..bdf2c707e9b 100644
--- a/mysql-test/suite/rpl/r/rpl_bug33931.result
+++ b/mysql-test/suite/rpl/r/rpl_bug33931.result
@@ -5,10 +5,11 @@ call mtr.add_suppression("Failed during slave I/O thread initialization");
 call mtr.add_suppression("Slave SQL.*Failed during slave thread initialization.* 1593");
 include/stop_slave.inc
 reset slave;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 SET GLOBAL debug_dbug="d,simulate_io_slave_error_on_init,simulate_sql_slave_error_on_init";
 start slave;
 include/wait_for_slave_sql_error.inc [errno=1593]
 Last_SQL_Error = 'Failed during slave thread initialization'
-SET GLOBAL debug_dbug="";
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 RESET SLAVE;
 include/rpl_end.inc
diff --git a/mysql-test/suite/rpl/r/rpl_bug41902.result b/mysql-test/suite/rpl/r/rpl_bug41902.result
index 8667795bd77..7d676ea73e3 100644
--- a/mysql-test/suite/rpl/r/rpl_bug41902.result
+++ b/mysql-test/suite/rpl/r/rpl_bug41902.result
@@ -2,6 +2,7 @@ include/master-slave.inc
 [connection master]
 connection slave;
 stop slave;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 SET @@debug_dbug="d,simulate_find_log_pos_error";
 reset slave;
 ERROR HY000: Target log not found in binlog index
@@ -19,6 +20,7 @@ SET @@debug_dbug="";
 reset slave;
 change master to master_host='dummy';
 connection master;
+SET @saved_dbug_m = @@global.debug_dbug;
 SET @@debug_dbug="d,simulate_find_log_pos_error";
 reset master;
 ERROR HY000: Target log not found in binlog index
@@ -29,6 +31,7 @@ purge binary logs to 'master-bin.000001';
 ERROR HY000: Target log not found in binlog index
 SET @@debug_dbug="";
 purge binary logs to 'master-bin.000001';
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 ==== clean up ====
 CHANGE MASTER TO MASTER_HOST = '127.0.0.1';
 include/rpl_end.inc
diff --git a/mysql-test/suite/rpl/r/rpl_checksum.result b/mysql-test/suite/rpl/r/rpl_checksum.result
index a74b688d722..21d8ca22feb 100644
--- a/mysql-test/suite/rpl/r/rpl_checksum.result
+++ b/mysql-test/suite/rpl/r/rpl_checksum.result
@@ -76,6 +76,7 @@ connection master;
 set @@global.binlog_checksum = CRC32;
 insert into t1 values (1) /* will not be applied on slave due to simulation */;
 connection slave;
+set @saved_dbug = @@global.debug_dbug;
 set @@global.debug_dbug='d,simulate_slave_unaware_checksum';
 start slave;
 include/wait_for_slave_io_error.inc [errno=1236]
@@ -83,15 +84,16 @@ Last_IO_Error = 'Got fatal error 1236 from master when reading data from binary
 select count(*) as zero from t1;
 zero
 0
-set @@global.debug_dbug='';
+set @@global.debug_dbug = @saved_dbug;
 connection slave;
 include/start_slave.inc
 connection master;
 set @@global.master_verify_checksum = 1;
+set @save_dbug = @@session.debug_dbug;
 set @@session.debug_dbug='d,simulate_checksum_test_failure';
 show binlog events;
 ERROR HY000: Error when executing command SHOW BINLOG EVENTS: Wrong offset or I/O error
-set @@session.debug_dbug='';
+SET debug_dbug= @save_dbug;
 set @@global.master_verify_checksum = default;
 connection slave;
 connection slave;
@@ -99,10 +101,11 @@ include/stop_slave.inc
 connection master;
 create table t2 (a int);
 connection slave;
+set @saved_dbug = @@global.debug_dbug;
 set @@global.debug_dbug='d,simulate_checksum_test_failure';
 start slave io_thread;
 include/wait_for_slave_io_error.inc [errno=1595,1913]
-set @@global.debug_dbug='';
+set @@global.debug_dbug = @saved_dbug;
 start slave io_thread;
 include/wait_for_slave_param.inc [Read_Master_Log_Pos]
 set @@global.slave_sql_verify_checksum = 1;
@@ -110,7 +113,7 @@ set @@global.debug_dbug='d,simulate_checksum_test_failure';
 start slave sql_thread;
 include/wait_for_slave_sql_error.inc [errno=1593]
 Last_SQL_Error = 'Error initializing relay log position: I/O error reading event at position 4'
-set @@global.debug_dbug='';
+set @@global.debug_dbug = @saved_dbug;
 include/start_slave.inc
 connection master;
 connection slave;
diff --git a/mysql-test/suite/rpl/r/rpl_corruption.result b/mysql-test/suite/rpl/r/rpl_corruption.result
index 25a82fd60cd..db72bb304fc 100644
--- a/mysql-test/suite/rpl/r/rpl_corruption.result
+++ b/mysql-test/suite/rpl/r/rpl_corruption.result
@@ -13,6 +13,7 @@ connection master;
 CREATE TABLE t1 (a INT NOT NULL PRIMARY KEY, b VARCHAR(10), c VARCHAR(100));
 include/stop_slave.inc
 # 2. Corruption in master binlog and SHOW BINLOG EVENTS
+set @saved_dbug = @@global.debug_dbug;
 SET GLOBAL debug_dbug="+d,corrupt_read_log_event_char";
 SHOW BINLOG EVENTS;
 ERROR HY000: Error when executing command SHOW BINLOG EVENTS: Wrong offset or I/O error
@@ -55,9 +56,9 @@ connection slave;
 include/diff_tables.inc [master:test.t1, slave:test.t1]
 # 8. Clean up
 connection master;
-SET GLOBAL debug_dbug= "";
+set @@global.debug_dbug = @saved_dbug;
 SET GLOBAL master_verify_checksum = @old_master_verify_checksum;
 DROP TABLE t1;
 connection slave;
-SET GLOBAL debug_dbug= "";
+set @@global.debug_dbug = @saved_dbug;
 include/rpl_end.inc
diff --git a/mysql-test/suite/rpl/r/rpl_heartbeat_debug.result b/mysql-test/suite/rpl/r/rpl_heartbeat_debug.result
index cf26c3bf04a..dc45c0b9ab3 100644
--- a/mysql-test/suite/rpl/r/rpl_heartbeat_debug.result
+++ b/mysql-test/suite/rpl/r/rpl_heartbeat_debug.result
@@ -7,7 +7,7 @@ set @@global.slave_net_timeout= 10;
 show status like 'Slave_heartbeat_period';;
 Variable_name	Slave_heartbeat_period
 Value	60.000
-SET @save_dbug= @@GLOBAL.debug_dbug;
+SET @saved_dbug= @@GLOBAL.debug_dbug;
 SET GLOBAL debug_dbug="+d,simulate_slave_heartbeat_network_error";
 CALL mtr.add_suppression('SET @master_heartbeat_period to master failed with error');
 CALL mtr.add_suppression('Master command COM_REGISTER_SLAVE failed: failed registering on master, reconnecting to try again');
@@ -25,7 +25,7 @@ connection master;
 drop table t1;
 connection slave;
 include/stop_slave.inc
-SET GLOBAL debug_dbug=@save_dbug;
+SET GLOBAL debug_dbug=@saved_dbug;
 set @@global.slave_net_timeout= @restore_slave_net_timeout;
 include/start_slave.inc
 include/rpl_end.inc
diff --git a/mysql-test/suite/rpl/r/rpl_incident.result b/mysql-test/suite/rpl/r/rpl_incident.result
index 8fb4aa907cc..6dbe4417c5a 100644
--- a/mysql-test/suite/rpl/r/rpl_incident.result
+++ b/mysql-test/suite/rpl/r/rpl_incident.result
@@ -14,6 +14,7 @@ a
 1
 2
 3
+set @saved_dbug = @@global.debug_dbug;
 SET GLOBAL debug_dbug= '+d,incident_database_resync_on_replace,*';
 REPLACE INTO t1 VALUES (4);
 SELECT * FROM t1;
@@ -22,6 +23,7 @@ a
 2
 3
 4
+set @@global.debug_dbug = @saved_dbug;
 connection slave;
 call mtr.add_suppression("Slave SQL.*The incident LOST_EVENTS occurred on the master.* 1590");
 include/wait_for_slave_sql_error.inc [errno=1590]
diff --git a/mysql-test/suite/rpl/r/rpl_init_slave_errors.result b/mysql-test/suite/rpl/r/rpl_init_slave_errors.result
index 91742814b4c..fc23734c645 100644
--- a/mysql-test/suite/rpl/r/rpl_init_slave_errors.result
+++ b/mysql-test/suite/rpl/r/rpl_init_slave_errors.result
@@ -4,12 +4,13 @@ connection slave;
 stop slave;
 reset slave;
 connection slave;
+set @saved_dbug = @@global.debug_dbug;
 SET GLOBAL debug_dbug= "d,simulate_io_slave_error_on_init,simulate_sql_slave_error_on_init";
 start slave;
 include/wait_for_slave_sql_error.inc [errno=1593]
 Last_SQL_Error = 'Failed during slave thread initialization'
 call mtr.add_suppression("Failed during slave.* thread initialization");
-SET GLOBAL debug_dbug= "";
+set @@global.debug_dbug = @saved_dbug;
 connection slave;
 reset slave;
 SET GLOBAL init_slave= "garbage";
diff --git a/mysql-test/suite/rpl/r/rpl_row_big_table_id.result b/mysql-test/suite/rpl/r/rpl_row_big_table_id.result
index 6fece52dda3..9a7a97e3d00 100644
--- a/mysql-test/suite/rpl/r/rpl_row_big_table_id.result
+++ b/mysql-test/suite/rpl/r/rpl_row_big_table_id.result
@@ -2,6 +2,7 @@ include/master-slave.inc
 [connection master]
 connection master;
 include/rpl_restart_server.inc [server_number=1]
+SET @saved_dbug = @@SESSION.debug_dbug;
 SET @@debug_dbug="d,simulate_big_table_id";
 CREATE TABLE t (a int);
 INSERT INTO t SET a= 0;
@@ -42,5 +43,6 @@ master-bin.000002	#	Query	1	#	COMMIT
 connection slave;
 connection master;
 DROP TABLE t;
+SET debug_dbug= @saved_dbug;
 connection slave;
 include/rpl_end.inc
diff --git a/mysql-test/suite/rpl/r/rpl_row_find_row_debug.result b/mysql-test/suite/rpl/r/rpl_row_find_row_debug.result
index 269dc16733a..f1a0059a04f 100644
--- a/mysql-test/suite/rpl/r/rpl_row_find_row_debug.result
+++ b/mysql-test/suite/rpl/r/rpl_row_find_row_debug.result
@@ -2,6 +2,7 @@ include/master-slave.inc
 [connection master]
 connection slave;
 include/stop_slave.inc
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 SET GLOBAL log_warnings = 2;
 SET GLOBAL debug_dbug="d,inject_long_find_row_note";
 include/start_slave.inc
@@ -18,7 +19,7 @@ connection slave;
 FOUND 1 /The slave is applying a ROW event on behalf of an UPDATE statement on table t1 and is currently taking a considerable amount/ in mysqld.2.err
 FOUND 1 /The slave is applying a ROW event on behalf of a DELETE statement on table t1 and is currently taking a considerable amount/ in mysqld.2.err
 include/stop_slave.inc
-SET GLOBAL debug_dbug = '';
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 SET GLOBAL log_warnings = 2;
 include/start_slave.inc
 include/rpl_end.inc
diff --git a/mysql-test/suite/rpl/r/rpl_semi_sync_skip_repl.result b/mysql-test/suite/rpl/r/rpl_semi_sync_skip_repl.result
index ec9607148d4..d517d53c6da 100644
--- a/mysql-test/suite/rpl/r/rpl_semi_sync_skip_repl.result
+++ b/mysql-test/suite/rpl/r/rpl_semi_sync_skip_repl.result
@@ -11,6 +11,7 @@ SET @@GLOBAL.rpl_semi_sync_slave_enabled = 1;
 include/start_slave.inc
 connection master;
 CREATE TABLE t1 (a INT) ENGINE=innodb;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 SET @@GLOBAL.debug_dbug="d,dbug_master_binlog_over_2GB";
 SET @@SESSION.skip_replication=1;
 INSERT INTO t1 SET a=1;
@@ -20,7 +21,7 @@ SET @@GLOBAL.debug_dbug="";
 FLUSH LOGS;
 connection slave;
 connection master;
-SET @@GLOBAL.debug_dbug=@@GLOBAL.debug_dbug;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 SET @@GLOBAL.rpl_semi_sync_master_timeout = 10000;
 SET @@GLOBAL.rpl_semi_sync_master_enabled = 0;
 connection master;
diff --git a/mysql-test/suite/rpl/r/rpl_show_slave_running.result b/mysql-test/suite/rpl/r/rpl_show_slave_running.result
index 729c718390a..353ff379776 100644
--- a/mysql-test/suite/rpl/r/rpl_show_slave_running.result
+++ b/mysql-test/suite/rpl/r/rpl_show_slave_running.result
@@ -3,6 +3,7 @@ include/master-slave.inc
 connection slave;
 SET DEBUG_SYNC= 'RESET';
 include/stop_slave.inc
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= 'd,dbug.before_get_running_status_yes';
 Slave_running, Slave_IO_Running, Slave_SQL_Running, must be OFF, NO, NO in three following queries
 SHOW STATUS LIKE 'Slave_running';
@@ -34,7 +35,7 @@ Slave_running	ON
 Slave_IO_Running= Yes
 Slave_SQL_Running= Yes
 connection slave;
-set global debug_dbug= '';
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 SET DEBUG_SYNC= 'RESET';
 End of tests
 include/rpl_end.inc
diff --git a/mysql-test/suite/rpl/r/rpl_slave_load_remove_tmpfile.result b/mysql-test/suite/rpl/r/rpl_slave_load_remove_tmpfile.result
index be2a17ea2b7..8f855813554 100644
--- a/mysql-test/suite/rpl/r/rpl_slave_load_remove_tmpfile.result
+++ b/mysql-test/suite/rpl/r/rpl_slave_load_remove_tmpfile.result
@@ -1,6 +1,7 @@
 include/master-slave.inc
 [connection master]
 connection slave;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 SET @@global.debug_dbug= '+d,remove_slave_load_file_before_write';
 connection master;
 create table t1(a int not null auto_increment, b int, primary key(a)) engine=innodb;
@@ -21,5 +22,5 @@ call mtr.add_suppression("Slave: Can't get stat of .*");
 call mtr.add_suppression("Slave SQL: Error .Can.t get stat of.* error.* 13");
 call mtr.add_suppression("Slave: File.* not found.*");
 call mtr.add_suppression("Slave SQL: Error .File.* not found.* error.* 29");
-SET @@global.debug_dbug= '';
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 include/rpl_end.inc
diff --git a/mysql-test/suite/rpl/r/rpl_stop_slave.result b/mysql-test/suite/rpl/r/rpl_stop_slave.result
index 4b9c544527b..a4dbf13290a 100644
--- a/mysql-test/suite/rpl/r/rpl_stop_slave.result
+++ b/mysql-test/suite/rpl/r/rpl_stop_slave.result
@@ -15,7 +15,7 @@ include/stop_slave.inc
 # Suspend the INSERT statement in current transaction on SQL thread.
 # It guarantees that SQL thread is applying the transaction when
 # STOP SLAVE command launchs.
-set @old_debug=@@global.debug;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= '+d,after_mysql_insert';
 include/start_slave.inc
 
@@ -75,6 +75,7 @@ connection master;
 connection slave;
 
 # Test end
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 include/restart_slave.inc
 connection slave;
 call mtr.add_suppression("Slave SQL.*Request to stop slave SQL Thread received while applying a group that has non-transactional changes; waiting for completion of the group");
@@ -99,7 +100,7 @@ connection slave;
 include/stop_slave.inc
 connection master;
 include/stop_dump_threads.inc
-set @old_debug=@@global.debug;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= '+d,dump_thread_wait_before_send_xid';
 connection slave;
 include/start_slave.inc
@@ -122,6 +123,7 @@ connection slave;
 include/wait_for_slave_to_stop.inc
 connection slave1;
 connection master;
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 include/stop_dump_threads.inc
 connection slave1;
 include/start_slave.inc
diff --git a/mysql-test/suite/rpl/r/rpl_view_debug.result b/mysql-test/suite/rpl/r/rpl_view_debug.result
index 497f4303698..1ec3dda9daa 100644
--- a/mysql-test/suite/rpl/r/rpl_view_debug.result
+++ b/mysql-test/suite/rpl/r/rpl_view_debug.result
@@ -21,6 +21,7 @@ Tables_in_test
 t1
 v1
 connection master;
+SET @saved_dbug = @@SESSION.debug_dbug;
 set @@debug_dbug="d,simulate_register_view_failure";
 CREATE VIEW v2 as SELECT * FROM t1;
 ERROR HY000: Out of memory.
@@ -36,4 +37,5 @@ v1
 connection master;
 DROP VIEW IF EXISTS v1;
 DROP TABLE t1;
+SET debug_dbug= @saved_dbug;
 include/rpl_end.inc
diff --git a/mysql-test/suite/rpl/t/kill_race_condition.test b/mysql-test/suite/rpl/t/kill_race_condition.test
index 0f3b44864fe..25a7b18bac2 100644
--- a/mysql-test/suite/rpl/t/kill_race_condition.test
+++ b/mysql-test/suite/rpl/t/kill_race_condition.test
@@ -7,6 +7,7 @@ create table t1 (a int);
 --sync_slave_with_master
 
 connection slave;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug='d,rows_log_event_before_open_table';
 
 connection master;
@@ -22,7 +23,7 @@ set debug_sync='now SIGNAL go_ahead_sql';
 --source include/wait_for_slave_sql_error.inc
 let $error= query_get_value(SHOW SLAVE STATUS, Last_SQL_Error, 1);
 --echo Last_SQL_Error = $error
-set global debug_dbug='';
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 set debug_sync='RESET';
 connection master;
 drop table t1;
diff --git a/mysql-test/suite/rpl/t/rpl_binlog_rollback_cleanup.test b/mysql-test/suite/rpl/t/rpl_binlog_rollback_cleanup.test
new file mode 100644
index 00000000000..ed4d713f626
--- /dev/null
+++ b/mysql-test/suite/rpl/t/rpl_binlog_rollback_cleanup.test
@@ -0,0 +1,46 @@
+# ==== Purpose ====
+#
+# Test verifies that when flushing an event to binary log fails the transaction
+# is successfully rolled back and following COMMIT command doesn't report any
+# assert.
+#
+# ==== Implementation ====
+#
+# Steps:
+#    0 - SET max_binlog_cache_size=64K
+#    1 - Create an Innodb table and insert required amount of data. Execute an
+#        UPDATE operation which generates a big update event whose size exceeds
+#        max_binlog_cache_size.
+#    2 - Wait for error 1197. Execute COMMIT command.
+#    3 - COMMIT should be successful.
+#
+# ==== References ====
+#
+# MDEV-18514: Assertion `!writer.checksum_len || writer.remains == 0' failed
+#
+--source include/have_innodb.inc
+--source include/have_binlog_format_row.inc
+--source include/master-slave.inc
+--connection master
+let $old_max_binlog_cache_size= query_get_value(SHOW VARIABLES LIKE "max_binlog_cache_size", Value, 1);
+SET GLOBAL max_binlog_cache_size = 65536;
+CREATE TABLE t1(a INT PRIMARY KEY, data VARCHAR(30000)) ENGINE=INNODB;
+let $data = `select concat('"', repeat('a',6000), '"')`;
+let $data1 = `select concat('"', repeat('b',6000), '"')`;
+--disable_query_log
+eval INSERT INTO t1 (a, data) VALUES (1, CONCAT($data, $data));
+eval INSERT INTO t1 (a, data) VALUES (2, CONCAT($data, $data));
+eval INSERT INTO t1 (a, data) VALUES (3, CONCAT($data, $data));
+eval INSERT INTO t1 (a, data) VALUES (4, CONCAT($data, $data));
+eval INSERT INTO t1 (a, data) VALUES (5, CONCAT($data, $data));
+START TRANSACTION;
+--error ER_TRANS_CACHE_FULL
+eval UPDATE t1 SET data=$data1;
+COMMIT;
+--enable_query_log
+
+--replace_result $old_max_binlog_cache_size ORIGINAL_VALUE
+--eval SET GLOBAL max_binlog_cache_size= $old_max_binlog_cache_size
+DROP TABLE t1;
+
+--source include/rpl_end.inc
diff --git a/mysql-test/suite/rpl/t/rpl_bug33931.test b/mysql-test/suite/rpl/t/rpl_bug33931.test
index 2273219a821..0b2cbb6365c 100644
--- a/mysql-test/suite/rpl/t/rpl_bug33931.test
+++ b/mysql-test/suite/rpl/t/rpl_bug33931.test
@@ -15,6 +15,7 @@ call mtr.add_suppression("Slave SQL.*Failed during slave thread initialization.*
 reset slave;
 
 # Set debug flags on slave to force errors to occur
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 SET GLOBAL debug_dbug="d,simulate_io_slave_error_on_init,simulate_sql_slave_error_on_init";
 
 --disable_query_log
@@ -39,7 +40,7 @@ start slave;
 #
 # Cleanup
 #
-SET GLOBAL debug_dbug="";
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 
 # Clear Last_SQL_Error
 RESET SLAVE;
diff --git a/mysql-test/suite/rpl/t/rpl_bug41902.test b/mysql-test/suite/rpl/t/rpl_bug41902.test
index fe9452b0eda..bb6c572580f 100644
--- a/mysql-test/suite/rpl/t/rpl_bug41902.test
+++ b/mysql-test/suite/rpl/t/rpl_bug41902.test
@@ -15,7 +15,7 @@ source include/master-slave.inc;
 
 connection slave;
 stop slave;
-
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 SET @@debug_dbug="d,simulate_find_log_pos_error";
 
 --error ER_UNKNOWN_TARGET_BINLOG
@@ -36,6 +36,7 @@ reset slave;
 change master to master_host='dummy';
 
 connection master;
+SET @saved_dbug_m = @@global.debug_dbug;
 SET @@debug_dbug="d,simulate_find_log_pos_error";
 --error ER_UNKNOWN_TARGET_BINLOG
 reset master;
@@ -53,10 +54,12 @@ purge binary logs to 'master-bin.000001';
 --disable_query_log
 call mtr.add_suppression("Failed to locate old binlog or relay log files");
 call mtr.add_suppression("MYSQL_BIN_LOG::purge_logs was called with file ..master-bin.000001 not listed in the index");
+set @@global.debug_dbug = @saved_dbug_m;
 connection slave;
 call mtr.add_suppression("Failed to locate old binlog or relay log files");
 call mtr.add_suppression("MYSQL_BIN_LOG::purge_logs was called with file ..master-bin.000001 not listed in the index");
 --enable_query_log
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 
 --echo ==== clean up ====
 CHANGE MASTER TO MASTER_HOST = '127.0.0.1';
diff --git a/mysql-test/suite/rpl/t/rpl_get_master_version_and_clock.test b/mysql-test/suite/rpl/t/rpl_get_master_version_and_clock.test
index 9c4cc1bc34d..02665c70b9e 100644
--- a/mysql-test/suite/rpl/t/rpl_get_master_version_and_clock.test
+++ b/mysql-test/suite/rpl/t/rpl_get_master_version_and_clock.test
@@ -26,7 +26,7 @@ call mtr.add_suppression("Fatal error: The slave I/O thread stops because master
 call mtr.add_suppression("Slave I/O thread .* register on master");
 
 #Test case 1: Try to get the value of the UNIX_TIMESTAMP from master under network disconnection
-let $debug_saved= `select @@global.debug`;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 
 # set up two parameters to pass into include/rpl_get_master_version_and_clock
 let $dbug_sync_point= 'debug_lock.before_get_UNIX_TIMESTAMP';
@@ -40,11 +40,9 @@ let $dbug_sync_point= 'debug_lock.before_get_SERVER_ID';
 let $debug_sync_action= 'now SIGNAL signal.get_server_id';
 source include/rpl_get_master_version_and_clock.test;
 
-eval set global debug_dbug= '$debug_saved';
-
 
 # cleanup
-
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 # is not really necessary but avoids mtr post-run env check warnings
 SET DEBUG_SYNC= 'RESET';
 
diff --git a/mysql-test/suite/rpl/t/rpl_heartbeat_debug.test b/mysql-test/suite/rpl/t/rpl_heartbeat_debug.test
index 6a426ed1e9f..bd66a249ada 100644
--- a/mysql-test/suite/rpl/t/rpl_heartbeat_debug.test
+++ b/mysql-test/suite/rpl/t/rpl_heartbeat_debug.test
@@ -18,7 +18,7 @@ set @@global.slave_net_timeout= 10;
 # default period slave_net_timeout/2
 #
 --query_vertical show status like 'Slave_heartbeat_period';
-SET @save_dbug= @@GLOBAL.debug_dbug;
+SET @saved_dbug= @@GLOBAL.debug_dbug;
 SET GLOBAL debug_dbug="+d,simulate_slave_heartbeat_network_error";
 CALL mtr.add_suppression('SET @master_heartbeat_period to master failed with error');
 CALL mtr.add_suppression('Master command COM_REGISTER_SLAVE failed: failed registering on master, reconnecting to try again');
@@ -44,7 +44,7 @@ drop table t1;
 connection slave;
 --source include/stop_slave.inc
 --disable_warnings
-SET GLOBAL debug_dbug=@save_dbug;
+SET GLOBAL debug_dbug=@saved_dbug;
 set @@global.slave_net_timeout= @restore_slave_net_timeout;
 --enable_warnings
 --source include/start_slave.inc
diff --git a/mysql-test/suite/rpl/t/rpl_row_big_table_id.test b/mysql-test/suite/rpl/t/rpl_row_big_table_id.test
index 0c6f9d5e862..abf22cc876e 100644
--- a/mysql-test/suite/rpl/t/rpl_row_big_table_id.test
+++ b/mysql-test/suite/rpl/t/rpl_row_big_table_id.test
@@ -17,6 +17,7 @@
 --let $rpl_server_number= 1
 --source include/rpl_restart_server.inc
 
+SET @saved_dbug = @@SESSION.debug_dbug;
 SET @@debug_dbug="d,simulate_big_table_id";
 CREATE TABLE t (a int);
 
@@ -51,7 +52,7 @@ if (`SELECT sum(a) != 6 FROM t`)
 
 --connection master
 DROP TABLE t;
-
+SET debug_dbug= @saved_dbug;
 --sync_slave_with_master
 
 --source include/rpl_end.inc
diff --git a/mysql-test/suite/rpl/t/rpl_row_find_row_debug.test b/mysql-test/suite/rpl/t/rpl_row_find_row_debug.test
index 9c0ee1cdbbb..e3edabe239d 100644
--- a/mysql-test/suite/rpl/t/rpl_row_find_row_debug.test
+++ b/mysql-test/suite/rpl/t/rpl_row_find_row_debug.test
@@ -9,7 +9,7 @@
 # - setup log_warnings and debug 
 --connection slave
 --source include/stop_slave.inc
---let $debug_save= `SELECT @@GLOBAL.debug_dbug`
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 --let $log_warnings_save= `SELECT @@GLOBAL.log_warnings`
 
 SET GLOBAL log_warnings = 2;
@@ -50,7 +50,7 @@ DROP TABLE t1;
 
 # cleanup
 --source include/stop_slave.inc
---eval SET GLOBAL debug_dbug = '$debug_save'
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 --eval SET GLOBAL log_warnings = $log_warnings_save
 --source include/start_slave.inc
 
diff --git a/mysql-test/suite/rpl/t/rpl_row_index_choice.test b/mysql-test/suite/rpl/t/rpl_row_index_choice.test
index 0ad9b315d66..958fa2352c2 100644
--- a/mysql-test/suite/rpl/t/rpl_row_index_choice.test
+++ b/mysql-test/suite/rpl/t/rpl_row_index_choice.test
@@ -47,6 +47,7 @@ sync_slave_with_master;
 connection slave;
 ANALYZE TABLE t2;
 --echo # Slave will crash if using the wrong or no index
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 SET GLOBAL debug_dbug="+d,slave_crash_if_wrong_index,slave_crash_if_table_scan";
 
 connection master;
@@ -238,6 +239,5 @@ connection master;
 DROP TABLE t1;
 sync_slave_with_master;
 connection slave;
-SET GLOBAL debug_dbug="";
-
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 --source include/rpl_end.inc
diff --git a/mysql-test/suite/rpl/t/rpl_semi_sync_skip_repl.test b/mysql-test/suite/rpl/t/rpl_semi_sync_skip_repl.test
index 8dd30b8a161..587e1290187 100644
--- a/mysql-test/suite/rpl/t/rpl_semi_sync_skip_repl.test
+++ b/mysql-test/suite/rpl/t/rpl_semi_sync_skip_repl.test
@@ -32,7 +32,7 @@ source include/start_slave.inc;
 CREATE TABLE t1 (a INT) ENGINE=innodb;
 
 # Make the following events as if they offset over 2GB from the beginning of binlog
---let $sav_debug_dbug=@@GLOBAL.debug_dbug
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 SET @@GLOBAL.debug_dbug="d,dbug_master_binlog_over_2GB";
 SET @@SESSION.skip_replication=1;
 INSERT INTO t1 SET a=1;
@@ -50,7 +50,7 @@ FLUSH LOGS;
 # Clean up
 #
 --connection master
---eval SET @@GLOBAL.debug_dbug=$sav_debug_dbug
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 --eval SET @@GLOBAL.rpl_semi_sync_master_timeout = $sav_timeout_master
 --eval SET @@GLOBAL.rpl_semi_sync_master_enabled = $sav_enabled_master
 
diff --git a/mysql-test/suite/rpl/t/rpl_show_slave_running.test b/mysql-test/suite/rpl/t/rpl_show_slave_running.test
index 2cb44fc6ac1..cb4a8819a5b 100644
--- a/mysql-test/suite/rpl/t/rpl_show_slave_running.test
+++ b/mysql-test/suite/rpl/t/rpl_show_slave_running.test
@@ -11,7 +11,7 @@ connection slave;
 
 SET DEBUG_SYNC= 'RESET';
 source include/stop_slave.inc;
-let $debug_saved= `select @@global.debug`;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= 'd,dbug.before_get_running_status_yes'; # to block due-started IO
 
 # Test 1. Slave is stopped
@@ -77,7 +77,7 @@ echo Slave_SQL_Running= $status;
 
 connection slave;
 
-eval set global debug_dbug= '$debug_saved';
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 SET DEBUG_SYNC= 'RESET';
 --echo End of tests
 --source include/rpl_end.inc
diff --git a/mysql-test/suite/rpl/t/rpl_slave_load_remove_tmpfile.test b/mysql-test/suite/rpl/t/rpl_slave_load_remove_tmpfile.test
index 69319bad4a0..100514089d5 100644
--- a/mysql-test/suite/rpl/t/rpl_slave_load_remove_tmpfile.test
+++ b/mysql-test/suite/rpl/t/rpl_slave_load_remove_tmpfile.test
@@ -29,7 +29,7 @@
 ##########################################################################
 
 connection slave;
---let $old_debug= `SELECT @@global.debug_dbug`
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 SET @@global.debug_dbug= '+d,remove_slave_load_file_before_write';
 
 connection master;
@@ -74,7 +74,7 @@ call mtr.add_suppression("Slave: File.* not found.*");
 call mtr.add_suppression("Slave SQL: Error .File.* not found.* error.* 29");
 --let $rpl_only_running_threads= 1
 
-eval SET @@global.debug_dbug= '$old_debug';
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 
 --source include/rpl_end.inc
 
diff --git a/mysql-test/suite/rpl/t/rpl_stop_slave.test b/mysql-test/suite/rpl/t/rpl_stop_slave.test
index 291524126ec..17efa7ade3b 100644
--- a/mysql-test/suite/rpl/t/rpl_stop_slave.test
+++ b/mysql-test/suite/rpl/t/rpl_stop_slave.test
@@ -22,7 +22,7 @@ source include/stop_slave.inc;
 --echo # Suspend the INSERT statement in current transaction on SQL thread.
 --echo # It guarantees that SQL thread is applying the transaction when
 --echo # STOP SLAVE command launchs.
-set @old_debug=@@global.debug;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= '+d,after_mysql_insert';
 source include/start_slave.inc;
 
@@ -44,9 +44,7 @@ source include/rpl_stop_slave.test;
 
 --echo
 --echo # Test end
---disable_query_log
-set global debug_dbug= @old_debug;
---enable_query_log
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 source include/restart_slave_sql.inc;
 
 connection slave;
@@ -79,7 +77,7 @@ connection master;
 # make sure that there are no zombie threads
 --source include/stop_dump_threads.inc
 
-set @old_debug=@@global.debug;
+SET @saved_dbug = @@GLOBAL.debug_dbug;
 set global debug_dbug= '+d,dump_thread_wait_before_send_xid';
 
 connection slave;
@@ -126,9 +124,7 @@ reap;
 # sure that we disable the DBUG_EXECUTE_IF
 # that would set the dump thread to wait
 connection master;
---disable_query_log
-set global debug_dbug= @old_debug;
---enable_query_log
+SET @@GLOBAL.debug_dbug = @saved_dbug;
 # make sure that there are no zombie threads
 --source include/stop_dump_threads.inc
 
diff --git a/mysql-test/suite/rpl/t/rpl_view_debug.test b/mysql-test/suite/rpl/t/rpl_view_debug.test
index a00b6733dea..0803692496e 100644
--- a/mysql-test/suite/rpl/t/rpl_view_debug.test
+++ b/mysql-test/suite/rpl/t/rpl_view_debug.test
@@ -18,6 +18,7 @@ sync_slave_with_master;
 # view already has to be on slave
 show tables;
 connection master;
+SET @saved_dbug = @@SESSION.debug_dbug;
 set @@debug_dbug="d,simulate_register_view_failure";
 
 --error ER_OUT_OF_RESOURCES
@@ -30,5 +31,5 @@ show tables;
 connection master;
 DROP VIEW IF EXISTS v1;
 DROP TABLE t1;
-
+SET debug_dbug= @saved_dbug;
 --source include/rpl_end.inc
diff --git a/mysql-test/suite/sys_vars/r/debug_dbug_func.result b/mysql-test/suite/sys_vars/r/debug_dbug_func.result
index 1c7ae4e2832..64b9c1a759b 100644
--- a/mysql-test/suite/sys_vars/r/debug_dbug_func.result
+++ b/mysql-test/suite/sys_vars/r/debug_dbug_func.result
@@ -1,13 +1,13 @@
 SET @old_debug = @@GLOBAL.debug;
-set debug_dbug= 'T';
+SET debug_dbug= 'T';
 select @@debug;
 @@debug
 T
-set debug_dbug= '+P';
+SET debug_dbug= '+P';
 select @@debug;
 @@debug
 P:T
-set debug_dbug= '-P';
+SET debug_dbug= '-P';
 select @@debug;
 @@debug
 T
diff --git a/mysql-test/suite/sys_vars/t/debug_dbug_func.test b/mysql-test/suite/sys_vars/t/debug_dbug_func.test
index b4cd4aefd5e..136a4c5504d 100644
--- a/mysql-test/suite/sys_vars/t/debug_dbug_func.test
+++ b/mysql-test/suite/sys_vars/t/debug_dbug_func.test
@@ -6,11 +6,11 @@ SET @old_debug = @@GLOBAL.debug;
 # Bug#34678 @@debug variable's incremental mode
 #
 
-set debug_dbug= 'T';
+SET debug_dbug= 'T';
 select @@debug;
-set debug_dbug= '+P';
+SET debug_dbug= '+P';
 select @@debug;
-set debug_dbug= '-P';
+SET debug_dbug= '-P';
 select @@debug;
 
 #
diff --git a/mysql-test/suite/wsrep/disabled.def b/mysql-test/suite/wsrep/disabled.def
index f4145211680..ab3f9fe3604 100644
--- a/mysql-test/suite/wsrep/disabled.def
+++ b/mysql-test/suite/wsrep/disabled.def
@@ -10,4 +10,4 @@
 #
 ##############################################################################
 
-
+variables : MDEV-17585 wsrep.variables
diff --git a/mysql-test/suite/wsrep/t/binlog_format.opt b/mysql-test/suite/wsrep/t/binlog_format.opt
index e3f2470c6e5..6504506e267 100644
--- a/mysql-test/suite/wsrep/t/binlog_format.opt
+++ b/mysql-test/suite/wsrep/t/binlog_format.opt
@@ -1 +1 @@
---innodb_autoinc_lock_mode=2 --wsrep-provider=$WSREP_PROVIDER --wsrep-cluster-address=gcomm://
+--innodb_autoinc_lock_mode=2 --wsrep-provider=$WSREP_PROVIDER --wsrep-cluster-address=gcomm:// --wsrep-on=1
diff --git a/sql/item_func.cc b/sql/item_func.cc
index bf4909e1846..e7be4211d19 100644
--- a/sql/item_func.cc
+++ b/sql/item_func.cc
@@ -123,7 +123,8 @@ Item_args::Item_args(THD *thd, const Item_args *other)
     arg_count= 0;
     return;
   }
-  memcpy(args, other->args, sizeof(Item*) * arg_count);
+  if (arg_count)
+    memcpy(args, other->args, sizeof(Item*) * arg_count);
 }
 
 
diff --git a/sql/log.cc b/sql/log.cc
index 900cc1b8197..0aac2ee61fb 100644
--- a/sql/log.cc
+++ b/sql/log.cc
@@ -484,6 +484,7 @@ private:
   void truncate(my_off_t pos, bool reset_cache=0)
   {
     DBUG_PRINT("info", ("truncating to position %lu", (ulong) pos));
+    cache_log.error=0;
     if (pending())
     {
       delete pending();
@@ -492,7 +493,7 @@ private:
     reinit_io_cache(&cache_log, WRITE_CACHE, pos, 0, reset_cache);
     cache_log.end_of_file= saved_max_binlog_cache_size;
   }
- 
+
   binlog_cache_data& operator=(const binlog_cache_data& info);
   binlog_cache_data(const binlog_cache_data& info);
 };
diff --git a/sql/sp_head.cc b/sql/sp_head.cc
index af4316085b7..3a113de9dd5 100644
--- a/sql/sp_head.cc
+++ b/sql/sp_head.cc
@@ -473,7 +473,7 @@ check_routine_name(const LEX_CSTRING *ident)
  *  sp_head
  *
  */
-
+ 
 sp_head *sp_head::create(sp_package *parent, const Sp_handler *handler)
 {
   MEM_ROOT own_root;
@@ -493,14 +493,20 @@ void sp_head::destroy(sp_head *sp)
   {
     /* Make a copy of main_mem_root as free_root will free the sp */
     MEM_ROOT own_root= sp->main_mem_root;
-    delete sp;
- 
     DBUG_PRINT("info", ("mem_root 0x%lx moved to 0x%lx",
                         (ulong) &sp->mem_root, (ulong) &own_root));
+    delete sp;
+
+ 
     free_root(&own_root, MYF(0));
   }
 }
 
+/*
+ *
+ *  sp_head
+ *
+ */
 
 sp_head::sp_head(MEM_ROOT *mem_root_arg, sp_package *parent, 
                  const Sp_handler *sph)
diff --git a/sql/sp_head.h b/sql/sp_head.h
index 7e00cf7a0d8..493bb777bdf 100644
--- a/sql/sp_head.h
+++ b/sql/sp_head.h
@@ -320,12 +320,10 @@ public:
 protected:
   sp_head(MEM_ROOT *mem_root, sp_package *parent, const Sp_handler *handler);
   virtual ~sp_head();
-
 public:
   static void destroy(sp_head *sp);
   static sp_head *create(sp_package *parent, const Sp_handler *handler);
 
-
   /// Initialize after we have reset mem_root
   void
   init(LEX *lex);
diff --git a/sql/sql_select.cc b/sql/sql_select.cc
index 76cad16de28..0d47aee9882 100644
--- a/sql/sql_select.cc
+++ b/sql/sql_select.cc
@@ -14543,15 +14543,18 @@ static int compare_fields_by_table_order(Item *field1,
 {
   int cmp= 0;
   bool outer_ref= 0;
-  Item_field *f1= (Item_field *) (field1->real_item());
-  Item_field *f2= (Item_field *) (field2->real_item());
-  if (field1->const_item() || f1->const_item())
+  Item *field1_real= field1->real_item();
+  Item *field2_real= field2->real_item();
+
+  if (field1->const_item() || field1_real->const_item())
     return -1;
-  if (field2->const_item() || f2->const_item())
+  if (field2->const_item() || field2_real->const_item())
     return 1;
+  Item_field *f1= (Item_field *) field1_real;
+  Item_field *f2= (Item_field *) field2_real;
   if (f1->used_tables() & OUTER_REF_TABLE_BIT)
   {
-    outer_ref= 1;
+    outer_ref= -1;
     cmp= -1;
   }
   if (f2->used_tables() & OUTER_REF_TABLE_BIT)
diff --git a/storage/innobase/buf/buf0dblwr.cc b/storage/innobase/buf/buf0dblwr.cc
index 3f998165ccc..55ce17513c2 100644
--- a/storage/innobase/buf/buf0dblwr.cc
+++ b/storage/innobase/buf/buf0dblwr.cc
@@ -1,7 +1,7 @@
 /*****************************************************************************
 
 Copyright (c) 1995, 2017, Oracle and/or its affiliates. All Rights Reserved.
-Copyright (c) 2013, 2019, MariaDB Corporation.
+Copyright (c) 2013, 2020, MariaDB Corporation.
 
 This program is free software; you can redistribute it and/or modify it under
 the terms of the GNU General Public License as published by the Free Software
@@ -989,6 +989,7 @@ try_again:
 		int64_t	sig_count = os_event_reset(buf_dblwr->b_event);
 		mutex_exit(&buf_dblwr->mutex);
 
+		os_aio_simulated_wake_handler_threads();
 		os_event_wait_low(buf_dblwr->b_event, sig_count);
 		goto try_again;
 	}
@@ -1118,6 +1119,7 @@ try_again:
 		checkpoint. */
 		int64_t	sig_count = os_event_reset(buf_dblwr->b_event);
 		mutex_exit(&buf_dblwr->mutex);
+		os_aio_simulated_wake_handler_threads();
 
 		os_event_wait_low(buf_dblwr->b_event, sig_count);
 		goto try_again;
diff --git a/storage/innobase/row/row0import.cc b/storage/innobase/row/row0import.cc
index 1d70d13190d..2d8f9405007 100644
--- a/storage/innobase/row/row0import.cc
+++ b/storage/innobase/row/row0import.cc
@@ -1152,60 +1152,82 @@ row_import::match_table_columns(
 
 			if (cfg_col->prtype != col->prtype) {
 				ib_errf(thd,
-					 IB_LOG_LEVEL_ERROR,
-					 ER_TABLE_SCHEMA_MISMATCH,
-					 "Column %s precise type mismatch.",
-					 col_name);
+					IB_LOG_LEVEL_ERROR,
+					ER_TABLE_SCHEMA_MISMATCH,
+					"Column %s precise type mismatch,"
+					" it's 0X%X in the table and 0X%X"
+					" in the tablespace meta file",
+					col_name, col->prtype, cfg_col->prtype);
 				err = DB_ERROR;
 			}
 
 			if (cfg_col->mtype != col->mtype) {
 				ib_errf(thd,
-					 IB_LOG_LEVEL_ERROR,
-					 ER_TABLE_SCHEMA_MISMATCH,
-					 "Column %s main type mismatch.",
-					 col_name);
+					IB_LOG_LEVEL_ERROR,
+					ER_TABLE_SCHEMA_MISMATCH,
+					"Column %s main type mismatch,"
+					" it's 0X%X in the table and 0X%X"
+					" in the tablespace meta file",
+					col_name, col->mtype, cfg_col->mtype);
 				err = DB_ERROR;
 			}
 
 			if (cfg_col->len != col->len) {
 				ib_errf(thd,
-					 IB_LOG_LEVEL_ERROR,
-					 ER_TABLE_SCHEMA_MISMATCH,
-					 "Column %s length mismatch.",
-					 col_name);
+					IB_LOG_LEVEL_ERROR,
+					ER_TABLE_SCHEMA_MISMATCH,
+					"Column %s length mismatch,"
+					" it's %u in the table and %u"
+					" in the tablespace meta file",
+					col_name, col->len, cfg_col->len);
 				err = DB_ERROR;
 			}
 
 			if (cfg_col->mbminlen != col->mbminlen
 			    || cfg_col->mbmaxlen != col->mbmaxlen) {
 				ib_errf(thd,
-					 IB_LOG_LEVEL_ERROR,
-					 ER_TABLE_SCHEMA_MISMATCH,
-					 "Column %s multi-byte len mismatch.",
-					 col_name);
+					IB_LOG_LEVEL_ERROR,
+					ER_TABLE_SCHEMA_MISMATCH,
+					"Column %s multi-byte len mismatch,"
+					" it's %u-%u in the table and %u-%u"
+					" in the tablespace meta file",
+					col_name, col->mbminlen, col->mbmaxlen,
+					cfg_col->mbminlen, cfg_col->mbmaxlen);
 				err = DB_ERROR;
 			}
 
 			if (cfg_col->ind != col->ind) {
+				ib_errf(thd,
+					IB_LOG_LEVEL_ERROR,
+					ER_TABLE_SCHEMA_MISMATCH,
+					"Column %s position mismatch,"
+					" it's %u in the table and %u"
+					" in the tablespace meta file",
+					col_name, col->ind, cfg_col->ind);
 				err = DB_ERROR;
 			}
 
 			if (cfg_col->ord_part != col->ord_part) {
 				ib_errf(thd,
-					 IB_LOG_LEVEL_ERROR,
-					 ER_TABLE_SCHEMA_MISMATCH,
-					 "Column %s ordering mismatch.",
-					 col_name);
+					IB_LOG_LEVEL_ERROR,
+					ER_TABLE_SCHEMA_MISMATCH,
+					"Column %s ordering mismatch,"
+					" it's %u in the table and %u"
+					" in the tablespace meta file",
+					col_name, col->ord_part,
+					cfg_col->ord_part);
 				err = DB_ERROR;
 			}
 
 			if (cfg_col->max_prefix != col->max_prefix) {
 				ib_errf(thd,
-					 IB_LOG_LEVEL_ERROR,
-					 ER_TABLE_SCHEMA_MISMATCH,
-					 "Column %s max prefix mismatch.",
-					 col_name);
+					IB_LOG_LEVEL_ERROR,
+					ER_TABLE_SCHEMA_MISMATCH,
+					"Column %s max prefix mismatch"
+					" it's %u in the table and %u"
+					" in the tablespace meta file",
+					col_name, col->max_prefix,
+					cfg_col->max_prefix);
 				err = DB_ERROR;
 			}
 		}
author	Sergei Petrunia <psergey@askmonty.org>	2020-01-17 00:46:40 +0300
committer	Sergei Petrunia <psergey@askmonty.org>	2020-01-17 00:46:40 +0300
commit	e709eb9bf712006d070767629518f827cd2f6bed (patch)
tree	103290899cbe2a67f78277e0e33486e51ef01717
parent	d531b4ee3a9bcd89a2fa6b49a2207eaf966f53e3 (diff)
parent	b04429434ad1ee7f49d263762a560f4ff31dd111 (diff)
download	mariadb-git-e709eb9bf712006d070767629518f827cd2f6bed.tar.gz