Merge 10.3 into 10.4, except MDEV-22543

Also, fix GCC -Og -Wmaybe-uninitialized in run_backup_stage()

41 files changed, 277 insertions, 216 deletions

diff --git a/extra/mariabackup/backup_copy.cc b/extra/mariabackup/backup_copy.cc
index 6a0674bf7f5..525481d5e9e 100644
--- a/extra/mariabackup/backup_copy.cc
+++ b/extra/mariabackup/backup_copy.cc
@@ -1782,7 +1782,7 @@ apply_log_finish()
 bool
 copy_back()
 {
-	bool ret;
+	bool ret = false;
 	datadir_iter_t *it = NULL;
 	datadir_node_t node;
 	char *dst_dir;
diff --git a/include/ilist.h b/include/ilist.h
index 822f0334022..6e7219937dd 100644
--- a/include/ilist.h
+++ b/include/ilist.h
@@ -19,6 +19,8 @@
 #ifndef ILIST_H
 #define ILIST_H
 
+#include "my_dbug.h"
+
 #include <cstddef>
 #include <iterator>
 
@@ -73,11 +75,13 @@ public:
     typedef T *pointer;
     typedef T &reference;
 
-    Iterator(ListNode *node) noexcept : node_(node) {}
+    Iterator(ListNode *node) noexcept : node_(node)
+    { DBUG_ASSERT(node_ != nullptr); }
 
     Iterator &operator++() noexcept
     {
       node_= node_->next;
+      DBUG_ASSERT(node_ != nullptr);
       return *this;
     }
     Iterator operator++(int) noexcept
@@ -90,6 +94,7 @@ public:
     Iterator &operator--() noexcept
     {
       node_= node_->prev;
+      DBUG_ASSERT(node_);
       return *this;
     }
     Iterator operator--(int) noexcept
@@ -184,8 +189,8 @@ public:
 
 #ifndef DBUG_OFF
     ListNode *curr= pos.node_;
-    curr->prev= NULL;
-    curr->next= NULL;
+    curr->prev= nullptr;
+    curr->next= nullptr;
 #endif
 
     return next;
diff --git a/mysql-test/main/type_datetime.result b/mysql-test/main/type_datetime.result
index 6dbf7e58d7b..bb3e86b6543 100644
--- a/mysql-test/main/type_datetime.result
+++ b/mysql-test/main/type_datetime.result
@@ -57,6 +57,7 @@ select * from t1;
 t
 0000-00-00 00:00:00
 drop table t1;
+SET TIMESTAMP=UNIX_TIMESTAMP('2020-08-11 00:00:01');
 CREATE TABLE t1 (a timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP, b date, c time, d datetime);
 insert into t1 (b,c,d) values(now(),curtime(),now());
 Warnings:
@@ -65,6 +66,7 @@ select date_format(a,"%Y-%m-%d")=b,right(a+0,6)=c+0,a=d+0 from t1;
 date_format(a,"%Y-%m-%d")=b	right(a+0,6)=c+0	a=d+0
 1	1	1
 drop table t1;
+SET TIMESTAMP=DEFAULT;
 CREATE TABLE t1 (a datetime not null);
 insert into t1 values (0);
 select * from t1 where a is null;
@@ -298,8 +300,10 @@ f2	f3
 select f2 from t1 where DATE(f2) between "2001-4-15" AND "01-4-15";
 f2
 2001-04-15 00:00:00
+SET timestamp=UNIX_TIMESTAMP('2001-01-01 00:00:01');
 SELECT 1 from dual where NOW() BETWEEN CURRENT_DATE() - INTERVAL 1 DAY AND CURRENT_DATE();
 1
+SET timestamp=DEFAULT;
 drop table t1;
 create table t1 (f1 date);
 insert into t1 values('01-01-01'),('01-01-02'),('01-01-03');
diff --git a/mysql-test/main/type_datetime.test b/mysql-test/main/type_datetime.test
index c8ad240d817..4fddf1c1a74 100644
--- a/mysql-test/main/type_datetime.test
+++ b/mysql-test/main/type_datetime.test
@@ -32,10 +32,12 @@ drop table t1;
 # Test insert of now() and curtime()
 #
 
+SET TIMESTAMP=UNIX_TIMESTAMP('2020-08-11 00:00:01');
 CREATE TABLE t1 (a timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP, b date, c time, d datetime);
 insert into t1 (b,c,d) values(now(),curtime(),now());
 select date_format(a,"%Y-%m-%d")=b,right(a+0,6)=c+0,a=d+0 from t1;
 drop table t1;
+SET TIMESTAMP=DEFAULT;
 
 #
 # Test of datetime and not null
@@ -201,6 +203,7 @@ drop table t1;
 #
 # Bug#16377: Wrong DATE/DATETIME comparison in BETWEEN function.
 #
+
 create table t1 (f1 date, f2 datetime, f3 timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP);
 insert into t1 values('2001-01-01','2001-01-01 01:01:01','2001-01-01 01:01:01');
 insert into t1 values('2001-02-05','2001-02-05 00:00:00','2001-02-05 01:01:01');
@@ -214,7 +217,9 @@ select f1, f2, f3 from t1 where cast(f1 as datetime) between f2 and
 select f2 from t1 where '2001-04-10 12:34:56' between f2 and '01-05-01';
 select f2, f3 from t1 where '01-03-10' between f2 and f3;
 select f2 from t1 where DATE(f2) between "2001-4-15" AND "01-4-15";
+SET timestamp=UNIX_TIMESTAMP('2001-01-01 00:00:01');
 SELECT 1 from dual where NOW() BETWEEN CURRENT_DATE() - INTERVAL 1 DAY AND CURRENT_DATE();
+SET timestamp=DEFAULT;
 drop table t1;
 
 #
diff --git a/mysql-test/suite/innodb/include/alter_table_pk_no_sort.inc b/mysql-test/suite/innodb/include/alter_table_pk_no_sort.inc
index 6a2fcd15be0..61e304a7626 100644
--- a/mysql-test/suite/innodb/include/alter_table_pk_no_sort.inc
+++ b/mysql-test/suite/innodb/include/alter_table_pk_no_sort.inc
@@ -263,3 +263,10 @@ create table t1(o1 int, o2 int, o3 int, primary key(o1,o2,o3)) engine = innodb;
 insert into t1 values(1,1,2),(2,2,1);
 alter table t1 drop primary key, add primary key(o1), lock=none;
 drop table t1;
+
+# pk(o1,o2) to pk(o1,o2,autoinc) must not sort
+create table t1(o1 int, o2 int, primary key(o1,o2)) engine = innodb;
+insert into t1 values(1,1),(2,1);
+alter table t1 drop primary key, add column a int unique auto_increment,
+add primary key(o1,o2,a), algorithm=inplace;
+drop table t1;
diff --git a/mysql-test/suite/innodb/r/alter_table.result b/mysql-test/suite/innodb/r/alter_table.result
index 0cfd3096f3f..c51c14314f1 100644
--- a/mysql-test/suite/innodb/r/alter_table.result
+++ b/mysql-test/suite/innodb/r/alter_table.result
@@ -53,6 +53,13 @@ ALTER TABLE t1 DROP a;
 ERROR HY000: Cannot drop index 'a': needed in a foreign key constraint
 ALTER TABLE t1 ADD c INT;
 DROP TABLE t1, tx;
+#
+# MDEV-14119 Assertion cmp_rec_rec() on ALTER TABLE
+#
+CREATE TABLE t1(a INT NOT NULL UNIQUE) ENGINE=InnoDB;
+INSERT INTO t1 SELECT * FROM seq_1_to_128;
+ALTER TABLE t1 ADD b TINYINT AUTO_INCREMENT PRIMARY KEY, DROP KEY a;
+DROP TABLE t1;
 create table t1 (a int) transactional=1 engine=aria;
 create table t2 (a int) transactional=1 engine=innodb;
 show create table t1;
diff --git a/mysql-test/suite/innodb/r/innodb-64k.result b/mysql-test/suite/innodb/r/innodb-64k.result
index 8f8e031bce2..f8dad893d0e 100644
--- a/mysql-test/suite/innodb/r/innodb-64k.result
+++ b/mysql-test/suite/innodb/r/innodb-64k.result
@@ -1081,3 +1081,10 @@ update t2 set col145=@b;
 COMMIT;
 drop table t2;
 DROP TABLE t1;
+#
+# MDEV-19526 heap number overflow
+#
+CREATE TABLE t1(a SMALLINT NOT NULL UNIQUE AUTO_INCREMENT, KEY(a))
+ENGINE=InnoDB;
+INSERT INTO t1 (a) SELECT seq FROM seq_1_to_8191;
+DROP TABLE t1;
diff --git a/mysql-test/suite/innodb/r/innodb-index-debug.result b/mysql-test/suite/innodb/r/innodb-index-debug.result
index 5d161e5e6ca..daef31d2caa 100644
--- a/mysql-test/suite/innodb/r/innodb-index-debug.result
+++ b/mysql-test/suite/innodb/r/innodb-index-debug.result
@@ -323,4 +323,9 @@ create table t1(o1 int, o2 int, o3 int, primary key(o1,o2,o3)) engine = innodb;
 insert into t1 values(1,1,2),(2,2,1);
 alter table t1 drop primary key, add primary key(o1), lock=none;
 drop table t1;
+create table t1(o1 int, o2 int, primary key(o1,o2)) engine = innodb;
+insert into t1 values(1,1),(2,1);
+alter table t1 drop primary key, add column a int unique auto_increment,
+add primary key(o1,o2,a), algorithm=inplace;
+drop table t1;
 SET DEBUG_DBUG = @saved_debug_dbug;
diff --git a/mysql-test/suite/innodb/r/innodb-index.result b/mysql-test/suite/innodb/r/innodb-index.result
index 4eba99950c7..7e58bfe38e5 100644
--- a/mysql-test/suite/innodb/r/innodb-index.result
+++ b/mysql-test/suite/innodb/r/innodb-index.result
@@ -1907,6 +1907,11 @@ create table t1(o1 int, o2 int, o3 int, primary key(o1,o2,o3)) engine = innodb;
 insert into t1 values(1,1,2),(2,2,1);
 alter table t1 drop primary key, add primary key(o1), lock=none;
 drop table t1;
+create table t1(o1 int, o2 int, primary key(o1,o2)) engine = innodb;
+insert into t1 values(1,1),(2,1);
+alter table t1 drop primary key, add column a int unique auto_increment,
+add primary key(o1,o2,a), algorithm=inplace;
+drop table t1;
 #
 # MDEV-15325 Incomplete validation of missing tablespace during recovery
 #
diff --git a/mysql-test/suite/innodb/t/alter_table.test b/mysql-test/suite/innodb/t/alter_table.test
index a8b52732c91..55c8626ae14 100644
--- a/mysql-test/suite/innodb/t/alter_table.test
+++ b/mysql-test/suite/innodb/t/alter_table.test
@@ -1,4 +1,5 @@
 --source include/have_innodb.inc
+--source include/have_sequence.inc
 #
 # MDEV-11995 ALTER TABLE proceeds despite reporting ER_TOO_LONG_KEY error
 #
@@ -60,6 +61,14 @@ ALTER TABLE t1 DROP a;
 ALTER TABLE t1 ADD c INT;
 DROP TABLE t1, tx;
 
+--echo #
+--echo # MDEV-14119 Assertion cmp_rec_rec() on ALTER TABLE
+--echo #
+CREATE TABLE t1(a INT NOT NULL UNIQUE) ENGINE=InnoDB;
+INSERT INTO t1 SELECT * FROM seq_1_to_128;
+ALTER TABLE t1 ADD b TINYINT AUTO_INCREMENT PRIMARY KEY, DROP KEY a;
+DROP TABLE t1;
+
 #
 # Check that innodb supports transactional=1
 #
diff --git a/mysql-test/suite/innodb/t/innodb-64k.test b/mysql-test/suite/innodb/t/innodb-64k.test
index b091eee6d57..62d7b929ba1 100644
--- a/mysql-test/suite/innodb/t/innodb-64k.test
+++ b/mysql-test/suite/innodb/t/innodb-64k.test
@@ -2,6 +2,7 @@
 # Tests for setting innodb-page-size=64k;
 --source include/have_innodb.inc
 --source include/have_innodb_64k.inc
+--source include/have_sequence.inc
 
 call mtr.add_suppression('InnoDB: Cannot add field.*because after adding it, the row size is');
 
@@ -638,3 +639,11 @@ COMMIT;
 
 drop table t2;
 DROP TABLE t1;
+
+--echo #
+--echo # MDEV-19526 heap number overflow
+--echo #
+CREATE TABLE t1(a SMALLINT NOT NULL UNIQUE AUTO_INCREMENT, KEY(a))
+ENGINE=InnoDB;
+INSERT INTO t1 (a) SELECT seq FROM seq_1_to_8191;
+DROP TABLE t1;
diff --git a/mysql-test/suite/sys_vars/r/sysvars_innodb.result b/mysql-test/suite/sys_vars/r/sysvars_innodb.result
index 9463f946e66..183dab52cbf 100644
--- a/mysql-test/suite/sys_vars/r/sysvars_innodb.result
+++ b/mysql-test/suite/sys_vars/r/sysvars_innodb.result
@@ -410,7 +410,7 @@ SESSION_VALUE	NULL
 DEFAULT_VALUE	zlib
 VARIABLE_SCOPE	GLOBAL
 VARIABLE_TYPE	ENUM
-VARIABLE_COMMENT	Compression algorithm used on page compression. One of: none, zlib, lz4, lzo, lzma, or bzip2
+VARIABLE_COMMENT	Compression algorithm used on page compression. One of: none, zlib, lz4, lzo, lzma, bzip2, or snappy
 NUMERIC_MIN_VALUE	NULL
 NUMERIC_MAX_VALUE	NULL
 NUMERIC_BLOCK_SIZE	NULL
diff --git a/plugin/handler_socket/CMakeLists.txt b/plugin/handler_socket/CMakeLists.txt
index 329ff58d7f2..5a1925b40e0 100644
--- a/plugin/handler_socket/CMakeLists.txt
+++ b/plugin/handler_socket/CMakeLists.txt
@@ -1,7 +1,8 @@
 
-IF(WIN32)
+IF(WIN32 OR WITHOUT_SERVER)
   # Handlersocket does not compile on Windows, compiles but does 
-  # not start on FreeBSD.  
+  # not start on FreeBSD.
+  # It is a server plugin and disable it explicitly here.
   RETURN()
 ENDIF()
 
diff --git a/plugin/server_audit/server_audit.c b/plugin/server_audit/server_audit.c
index c8b22eee20c..4a6757aee90 100644
--- a/plugin/server_audit/server_audit.c
+++ b/plugin/server_audit/server_audit.c
@@ -1431,7 +1431,6 @@ static size_t escape_string_hide_passwords(const char *str, unsigned int len,
   const char *res_start= result;
   const char *res_end= result + result_len - 2;
   size_t d_len;
-  char b_char;
 
   while (len)
   {
@@ -1469,27 +1468,28 @@ static size_t escape_string_hide_passwords(const char *str, unsigned int len,
 
       if (*next_s)
       {
-        memmove(result + d_len, "*****", 5);
+        const char b_char= *next_s++;
+        memset(result + d_len, '*', 5);
         result+= d_len + 5;
-        b_char= *(next_s++);
-      }
-      else
-        result+= d_len;
 
-      while (*next_s)
-      {
-        if (*next_s == b_char)
-        {
-          ++next_s;
-          break;
-        }
-        if (*next_s == '\\')
+        while (*next_s)
         {
-          if (next_s[1])
-            next_s++;
+          if (*next_s == b_char)
+          {
+            ++next_s;
+            break;
+          }
+          if (*next_s == '\\')
+          {
+            if (next_s[1])
+              next_s++;
+          }
+          next_s++;
         }
-        next_s++;
       }
+      else
+        result+= d_len;
+
       len-= (uint)(next_s - str);
       str= next_s;
       continue;
@@ -1497,19 +1497,23 @@ static size_t escape_string_hide_passwords(const char *str, unsigned int len,
 no_password:
     if (result >= res_end)
       break;
-    if ((b_char= escaped_char(*str)))
+    else
     {
-      if (result+1 >= res_end)
-        break;
-      *(result++)= '\\';
-      *(result++)= b_char;
+      const char b_char= escaped_char(*str);
+      if (b_char)
+      {
+        if (result+1 >= res_end)
+          break;
+        *(result++)= '\\';
+        *(result++)= b_char;
+      }
+      else if (is_space(*str))
+        *(result++)= ' ';
+      else
+        *(result++)= *str;
+      str++;
+      len--;
     }
-    else if (is_space(*str))
-      *(result++)= ' ';
-    else
-      *(result++)= *str;
-    str++;
-    len--;
   }
   *result= 0;
   return result - res_start;
diff --git a/scripts/mysqld_multi.sh b/scripts/mysqld_multi.sh
index 2c3578834eb..0b33f61710e 100644
--- a/scripts/mysqld_multi.sh
+++ b/scripts/mysqld_multi.sh
@@ -308,9 +308,7 @@ sub report_mysqlds
 
 sub start_mysqlds()
 {
-  my (@groups, $com, $tmp, $i, @options, $j, $mysqld_found, $suffix_found, $info_sent);
-
-  $suffix_found= 0;
+  my (@groups, $com, $tmp, $i, @options, $j, $mysqld_found, $info_sent);
 
   if (!$opt_no_log)
   {
@@ -349,10 +347,6 @@ sub start_mysqlds()
         $options[$j]= quote_shell_word($options[$j]);
         $tmp.= " $options[$j]";
       }
-      elsif ("--defaults-group-suffix=" eq substr($options[$j], 0, 24))
-      {
-        $suffix_found= 1;
-      }
       else
       {
 	$options[$j]= quote_shell_word($options[$j]);
@@ -369,12 +363,6 @@ sub start_mysqlds()
       $info_sent= 1;
     }
 
-    if (!$suffix_found)
-    {
-      $com.= " --defaults-group-suffix=";
-      $com.= substr($groups[$i],6);
-    }
-
     $com.= $tmp;
 
     if ($opt_wsrep_new_cluster) {
diff --git a/scripts/wsrep_sst_mariabackup.sh b/scripts/wsrep_sst_mariabackup.sh
index 1991fe4dd8d..63ff5646535 100644
--- a/scripts/wsrep_sst_mariabackup.sh
+++ b/scripts/wsrep_sst_mariabackup.sh
@@ -712,7 +712,8 @@ INNODB_DATA_HOME_DIR=${INNODB_DATA_HOME_DIR:-""}
 if [ ! -z "$INNODB_DATA_HOME_DIR_ARG" ]; then
     INNODB_DATA_HOME_DIR=$INNODB_DATA_HOME_DIR_ARG
 fi
-# if INNODB_DATA_HOME_DIR env. variable is not set, try to get it from my.cnf
+# if no command line arg and INNODB_DATA_HOME_DIR environment variable
+# is not set, try to get it from my.cnf:
 if [ -z "$INNODB_DATA_HOME_DIR" ]; then
     INNODB_DATA_HOME_DIR=$(parse_cnf mysqld$WSREP_SST_OPT_SUFFIX_VALUE innodb-data-home-dir '')
 fi
@@ -951,17 +952,25 @@ then
 
     ib_home_dir=$INNODB_DATA_HOME_DIR
 
-    # Try to set ib_log_dir from the command line:
-    ib_log_dir=$INNODB_LOG_GROUP_HOME_ARG
-    if [ -z "$ib_log_dir" ]; then
-        ib_log_dir=$(parse_cnf mysqld$WSREP_SST_OPT_SUFFIX_VALUE innodb-log-group-home-dir "")
+    WSREP_LOG_DIR=${WSREP_LOG_DIR:-""}
+    # Try to set WSREP_LOG_DIR from the command line:
+    if [ ! -z "$INNODB_LOG_GROUP_HOME_ARG" ]; then
+        WSREP_LOG_DIR=$INNODB_LOG_GROUP_HOME_ARG
     fi
-    if [ -z "$ib_log_dir" ]; then
-        ib_log_dir=$(parse_cnf --mysqld innodb-log-group-home-dir "")
+    # if no command line arg and WSREP_LOG_DIR is not set,
+    # try to get it from my.cnf:
+    if [ -z "$WSREP_LOG_DIR" ]; then
+        WSREP_LOG_DIR=$(parse_cnf mysqld$WSREP_SST_OPT_SUFFIX_VALUE innodb-log-group-home-dir '')
     fi
+    if [ -z "$WSREP_LOG_DIR" ]; then
+        WSREP_LOG_DIR=$(parse_cnf --mysqld innodb-log-group-home-dir '')
+    fi
+
+    ib_log_dir=$WSREP_LOG_DIR
 
     # Try to set ib_undo_dir from the command line:
-    ib_undo_dir=$INNODB_UNDO_DIR_ARG
+    ib_undo_dir=${INNODB_UNDO_DIR_ARG:-""}
+    # if no command line arg then try to get it from my.cnf:
     if [ -z "$ib_undo_dir" ]; then
         ib_undo_dir=$(parse_cnf mysqld$WSREP_SST_OPT_SUFFIX_VALUE innodb-undo-directory "")
     fi
diff --git a/scripts/wsrep_sst_rsync.sh b/scripts/wsrep_sst_rsync.sh
index 96e542ce844..d42cf014009 100644
--- a/scripts/wsrep_sst_rsync.sh
+++ b/scripts/wsrep_sst_rsync.sh
@@ -152,10 +152,11 @@ fi
 
 WSREP_LOG_DIR=${WSREP_LOG_DIR:-""}
 # Try to set WSREP_LOG_DIR from the command line:
-if [ -z "$WSREP_LOG_DIR" ]; then
+if [ ! -z "$INNODB_LOG_GROUP_HOME_ARG" ]; then
     WSREP_LOG_DIR=$INNODB_LOG_GROUP_HOME_ARG
 fi
-# if WSREP_LOG_DIR env. variable is not set, try to get it from my.cnf
+# if no command line arg and WSREP_LOG_DIR is not set,
+# try to get it from my.cnf:
 if [ -z "$WSREP_LOG_DIR" ]; then
     WSREP_LOG_DIR=$(parse_cnf mysqld$WSREP_SST_OPT_SUFFIX_VALUE innodb-log-group-home-dir '')
 fi
@@ -176,7 +177,8 @@ INNODB_DATA_HOME_DIR=${INNODB_DATA_HOME_DIR:-""}
 if [ ! -z "$INNODB_DATA_HOME_DIR_ARG" ]; then
     INNODB_DATA_HOME_DIR=$INNODB_DATA_HOME_DIR_ARG
 fi
-# if INNODB_DATA_HOME_DIR env. variable is not set, try to get it from my.cnf
+# if no command line arg and INNODB_DATA_HOME_DIR environment variable
+# is not set, try to get it from my.cnf:
 if [ -z "$INNODB_DATA_HOME_DIR" ]; then
     INNODB_DATA_HOME_DIR=$(parse_cnf mysqld$WSREP_SST_OPT_SUFFIX_VALUE innodb-data-home-dir '')
 fi
diff --git a/sql/backup.cc b/sql/backup.cc
index 5976506cf92..813485ea29a 100644
--- a/sql/backup.cc
+++ b/sql/backup.cc
@@ -1,4 +1,4 @@
-/* Copyright (c) 2018, MariaDB Corporation
+/* Copyright (c) 2018, 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 Foundation; version 2 of the License.
@@ -96,7 +96,7 @@ bool run_backup_stage(THD *thd, backup_stages stage)
 
   do
   {
-    bool res;
+    bool res= false;
     backup_stages previous_stage= thd->current_backup_stage;
     thd->current_backup_stage= next_stage;
     switch (next_stage) {
@@ -120,7 +120,6 @@ bool run_backup_stage(THD *thd, backup_stages stage)
       break;
     case BACKUP_FINISHED:
       DBUG_ASSERT(0);
-      res= 0;
     }
     if (res)
     {
diff --git a/sql/ha_partition.cc b/sql/ha_partition.cc
index b767045fa26..f745acda75f 100644
--- a/sql/ha_partition.cc
+++ b/sql/ha_partition.cc
@@ -9593,7 +9593,6 @@ double ha_partition::read_time(uint index, uint ranges, ha_rows rows)
 
 ha_rows ha_partition::records()
 {
-  int error;
   ha_rows tot_rows= 0;
   uint i;
   DBUG_ENTER("ha_partition::records");
@@ -9602,9 +9601,10 @@ ha_rows ha_partition::records()
        i < m_tot_parts;
        i= bitmap_get_next_set(&m_part_info->read_partitions, i))
   {
-    ha_rows rows;
-    if (unlikely((error= m_file[i]->pre_records()) ||
-                 (rows= m_file[i]->records()) == HA_POS_ERROR))
+    if (unlikely(m_file[i]->pre_records()))
+      DBUG_RETURN(HA_POS_ERROR);
+    const ha_rows rows= m_file[i]->records();
+    if (unlikely(rows == HA_POS_ERROR))
       DBUG_RETURN(HA_POS_ERROR);
     tot_rows+= rows;
   }
diff --git a/sql/item.cc b/sql/item.cc
index 61651323626..f8c29c8974c 100644
--- a/sql/item.cc
+++ b/sql/item.cc
@@ -7475,7 +7475,6 @@ Item *find_producing_item(Item *item, st_select_lex *sel)
   DBUG_ASSERT(item->type() == Item::FIELD_ITEM ||
               (item->type() == Item::REF_ITEM &&
                ((Item_ref *) item)->ref_type() == Item_ref::VIEW_REF)); 
-  Item *producing_item;
   Item_field *field_item= NULL;
   Item_equal *item_equal= item->get_item_equal();
   table_map tab_map= sel->master_unit()->derived->table->map;
@@ -7497,6 +7496,7 @@ Item *find_producing_item(Item *item, st_select_lex *sel)
   List_iterator_fast<Item> li(sel->item_list);
   if (field_item)
   {
+    Item *producing_item= NULL;
     uint field_no= field_item->field->field_index;
     for (uint i= 0; i <= field_no; i++)
       producing_item= li++;
diff --git a/sql/item_geofunc.cc b/sql/item_geofunc.cc
index 9e6c8ea9008..ce52c6d246d 100644
--- a/sql/item_geofunc.cc
+++ b/sql/item_geofunc.cc
@@ -2380,12 +2380,15 @@ double Item_func_distance::val_real()
   MBR mbr1, mbr2;
   const char *c_end;
 
-
-  if ((null_value= (args[0]->null_value || args[1]->null_value ||
-          !(g1= Geometry::construct(&buffer1, res1->ptr(), res1->length())) ||
-          !(g2= Geometry::construct(&buffer2, res2->ptr(), res2->length())) ||
-          g1->get_mbr(&mbr1, &c_end) ||
-          g2->get_mbr(&mbr2, &c_end))))
+  if (args[0]->null_value || args[1]->null_value)
+    goto mem_error;
+  g1= Geometry::construct(&buffer1, res1->ptr(), res1->length());
+  if (!g1)
+    goto mem_error;
+  g2= Geometry::construct(&buffer2, res2->ptr(), res2->length());
+  if (!g2)
+    goto mem_error;
+  if (g1->get_mbr(&mbr1, &c_end) || g2->get_mbr(&mbr2, &c_end))
     goto mem_error;
 
   mbr1.add_mbr(&mbr2);
@@ -2534,7 +2537,7 @@ String *Item_func_pointonsurface::val_str(String *str)
   Geometry *g;
   MBR mbr;
   const char *c_end;
-  double UNINIT_VAR(px), UNINIT_VAR(py), x0, y0;
+  double UNINIT_VAR(px), UNINIT_VAR(py), x0, UNINIT_VAR(y0);
   String *result= 0;
   const Gcalc_scan_iterator::point *pprev= NULL;
   uint32 srid;
diff --git a/sql/item_strfunc.cc b/sql/item_strfunc.cc
index a61de0dfdaf..c735f697986 100644
--- a/sql/item_strfunc.cc
+++ b/sql/item_strfunc.cc
@@ -1,6 +1,6 @@
 /*
    Copyright (c) 2000, 2017, Oracle and/or its affiliates.
-   Copyright (c) 2009, 2019, MariaDB Corporation
+   Copyright (c) 2009, 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
@@ -646,7 +646,7 @@ String *Item_func_concat_operator_oracle::val_str(String *str)
 {
   DBUG_ASSERT(fixed == 1);
   THD *thd= current_thd;
-  String *res;
+  String *res= NULL;
   uint i;
 
   null_value=0;
@@ -656,7 +656,7 @@ String *Item_func_concat_operator_oracle::val_str(String *str)
     if ((res= args[i]->val_str(str)))
       break;
   }
-  if (i == arg_count)
+  if (!res)
     goto null;
 
   if (res != str)
diff --git a/sql/sql_repl.cc b/sql/sql_repl.cc
index 1080018b84d..d1c122ba7a5 100644
--- a/sql/sql_repl.cc
+++ b/sql/sql_repl.cc
@@ -375,11 +375,15 @@ static int send_file(THD *thd)
     We need net_flush here because the client will not know it needs to send
     us the file name until it has processed the load event entry
   */
-  if (unlikely(net_flush(net) || (packet_len = my_net_read(net)) == packet_error))
+  if (unlikely(net_flush(net)))
   {
+  read_error:
     errmsg = "while reading file name";
     goto err;
   }
+  packet_len= my_net_read(net);
+  if (unlikely(packet_len == packet_error))
+    goto read_error;
 
   // terminate with \0 for fn_format
   *((char*)net->read_pos +  packet_len) = 0;
diff --git a/sql/sql_yacc.yy b/sql/sql_yacc.yy
index 3adc2801270..14b7a5589e1 100644
--- a/sql/sql_yacc.yy
+++ b/sql/sql_yacc.yy
@@ -4394,9 +4394,11 @@ sp_fetch_list:
             LEX *lex= Lex;
             sp_head *sp= lex->sphead;
             sp_pcontext *spc= lex->spcont;
-            sp_variable *spv;
+            sp_variable *spv= likely(spc != NULL)
+              ? spc->find_variable(&$1, false)
+              : NULL;
 
-            if (unlikely(!spc || !(spv = spc->find_variable(&$1, false))))
+            if (unlikely(!spv))
               my_yyabort_error((ER_SP_UNDECLARED_VAR, MYF(0), $1.str));
 
             /* An SP local variable */
@@ -4408,9 +4410,11 @@ sp_fetch_list:
             LEX *lex= Lex;
             sp_head *sp= lex->sphead;
             sp_pcontext *spc= lex->spcont;
-            sp_variable *spv;
+            sp_variable *spv= likely(spc != NULL)
+              ? spc->find_variable(&$3, false)
+              : NULL;
 
-            if (unlikely(!spc || !(spv = spc->find_variable(&$3, false))))
+            if (unlikely(!spv))
               my_yyabort_error((ER_SP_UNDECLARED_VAR, MYF(0), $3.str));
 
             /* An SP local variable */
diff --git a/sql/sql_yacc_ora.yy b/sql/sql_yacc_ora.yy
index fdb3e90a509..9366a7bcd9f 100644
--- a/sql/sql_yacc_ora.yy
+++ b/sql/sql_yacc_ora.yy
@@ -4310,9 +4310,10 @@ sp_fetch_list:
             LEX *lex= Lex;
             sp_head *sp= lex->sphead;
             sp_pcontext *spc= lex->spcont;
-            sp_variable *spv;
-
-            if (unlikely(!spc || !(spv = spc->find_variable(&$1, false))))
+            sp_variable *spv= likely(spc != NULL)
+              ? spc->find_variable(&$1, false)
+              : NULL;
+            if (unlikely(!spv))
               my_yyabort_error((ER_SP_UNDECLARED_VAR, MYF(0), $1.str));
 
             /* An SP local variable */
@@ -4324,9 +4325,10 @@ sp_fetch_list:
             LEX *lex= Lex;
             sp_head *sp= lex->sphead;
             sp_pcontext *spc= lex->spcont;
-            sp_variable *spv;
-
-            if (unlikely(!spc || !(spv = spc->find_variable(&$3, false))))
+            sp_variable *spv= likely(spc != NULL)
+              ? spc->find_variable(&$3, false)
+              : NULL;
+            if (unlikely(!spv))
               my_yyabort_error((ER_SP_UNDECLARED_VAR, MYF(0), $3.str));
 
             /* An SP local variable */
diff --git a/sql/threadpool_generic.cc b/sql/threadpool_generic.cc
index 6d6b22d5900..3f4997b8238 100644
--- a/sql/threadpool_generic.cc
+++ b/sql/threadpool_generic.cc
@@ -1079,7 +1079,10 @@ void thread_group_destroy(thread_group_t *thread_group)
 #endif
 
   if (!--shutdown_group_count)
+  {
     my_free(all_groups);
+    all_groups= 0;
+  }
 }
 
 /**
@@ -1675,6 +1678,14 @@ TP_pool_generic::~TP_pool_generic()
   {
     thread_group_close(&all_groups[i]);
   }
+
+  /*
+    Wait until memory occupied by all_groups is freed.
+  */
+  int timeout_ms=5000;
+  while(all_groups && timeout_ms--)
+    my_sleep(1000);
+
   threadpool_started= false;
   DBUG_VOID_RETURN;
 }
diff --git a/storage/innobase/btr/btr0cur.cc b/storage/innobase/btr/btr0cur.cc
index 5696d184386..0dae73c56d7 100644
--- a/storage/innobase/btr/btr0cur.cc
+++ b/storage/innobase/btr/btr0cur.cc
@@ -3510,17 +3510,23 @@ fail_err:
 	}
 
 	ulint	max_size = page_get_max_insert_size_after_reorganize(page, 1);
+	if (max_size < rec_size) {
+		goto fail;
+	}
+
+	const ulint n_recs = page_get_n_recs(page);
+	if (UNIV_UNLIKELY(n_recs >= 8189)) {
+		ut_ad(srv_page_size == 65536);
+		goto fail;
+	}
 
 	if (page_has_garbage(page)) {
-		if ((max_size < rec_size
-		     || max_size < BTR_CUR_PAGE_REORGANIZE_LIMIT)
-		    && page_get_n_recs(page) > 1
+		if (max_size < BTR_CUR_PAGE_REORGANIZE_LIMIT
+		    && n_recs > 1
 		    && page_get_max_insert_size(page, 1) < rec_size) {
 
 			goto fail;
 		}
-	} else if (max_size < rec_size) {
-		goto fail;
 	}
 
 	/* If there have been many consecutive inserts to the
diff --git a/storage/innobase/buf/buf0rea.cc b/storage/innobase/buf/buf0rea.cc
index ae9ecf7d81b..9bd1b16a0a2 100644
--- a/storage/innobase/buf/buf0rea.cc
+++ b/storage/innobase/buf/buf0rea.cc
@@ -265,24 +265,6 @@ buf_read_ahead_random(const page_id_t page_id, ulint zip_size, bool ibuf)
 		* buf_read_ahead_random_area;
 
 	if (fil_space_t* space = fil_space_acquire(page_id.space())) {
-#ifdef UNIV_DEBUG
-		if (srv_file_per_table) {
-			ulint	size = 0;
-			const ulint physical_size = space->physical_size();
-
-			for (const fil_node_t*	node =
-				UT_LIST_GET_FIRST(space->chain);
-			     node != NULL;
-			     node = UT_LIST_GET_NEXT(chain, node)) {
-
-				size += ulint(os_file_get_size(node->handle)
-					/ physical_size);
-			}
-
-			ut_ad(size == space->size);
-		}
-#endif /* UNIV_DEBUG */
-
 		high = space->max_page_number_for_io(high);
 		space->release();
 	} else {
diff --git a/storage/innobase/fil/fil0crypt.cc b/storage/innobase/fil/fil0crypt.cc
index 7c4046871cc..7ae2f42ed57 100644
--- a/storage/innobase/fil/fil0crypt.cc
+++ b/storage/innobase/fil/fil0crypt.cc
@@ -1589,28 +1589,31 @@ inline fil_space_t *fil_system_t::keyrotate_next(fil_space_t *space,
   ut_ad(mutex_own(&mutex));
 
   sized_ilist<fil_space_t, rotation_list_tag_t>::iterator it=
-    space ? space : rotation_list.begin();
+    space && space->is_in_rotation_list ? space : rotation_list.begin();
   const sized_ilist<fil_space_t, rotation_list_tag_t>::iterator end=
     rotation_list.end();
 
   if (space)
   {
-    while (++it != end && (!UT_LIST_GET_LEN(it->chain) || it->is_stopping()));
+    const bool released= !space->release();
 
-    /* If one of the encryption threads already started the encryption
-    of the table then don't remove the unencrypted spaces from rotation list
-
-    If there is a change in innodb_encrypt_tables variables value then
-    don't remove the last processed tablespace from the rotation list. */
-    space->release();
-
-    if (!space->referenced() &&
-        (!recheck || space->crypt_data) && !encrypt == !srv_encrypt_tables &&
-        space->is_in_rotation_list)
+    if (space->is_in_rotation_list)
     {
-      ut_a(!rotation_list.empty());
-      rotation_list.remove(*space);
-      space->is_in_rotation_list= false;
+      while (++it != end &&
+             (!UT_LIST_GET_LEN(it->chain) || it->is_stopping()));
+
+      /* If one of the encryption threads already started the encryption
+      of the table then don't remove the unencrypted spaces from rotation list
+
+      If there is a change in innodb_encrypt_tables variables value then
+      don't remove the last processed tablespace from the rotation list. */
+      if (released && (!recheck || space->crypt_data) &&
+          !encrypt == !srv_encrypt_tables)
+      {
+        ut_a(!rotation_list.empty());
+        rotation_list.remove(*space);
+        space->is_in_rotation_list= false;
+      }
     }
   }
 
diff --git a/storage/innobase/fil/fil0pagecompress.cc b/storage/innobase/fil/fil0pagecompress.cc
index b3390a4cd12..1d38f9dc6b7 100644
--- a/storage/innobase/fil/fil0pagecompress.cc
+++ b/storage/innobase/fil/fil0pagecompress.cc
@@ -1,6 +1,6 @@
 /*****************************************************************************
 
-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
@@ -252,15 +252,6 @@ fail:
 		memset(out_buf + tmp, 0, write_size - tmp);
 	}
 
-#ifdef UNIV_DEBUG
-	/* Verify that page can be decompressed */
-	{
-		page_t tmp_buf[UNIV_PAGE_SIZE_MAX];
-		page_t page[UNIV_PAGE_SIZE_MAX];
-		memcpy(page, out_buf, write_size);
-		ut_ad(fil_page_decompress(tmp_buf, page, flags));
-	}
-#endif
 	srv_stats.page_compression_saved.add(srv_page_size - write_size);
 	srv_stats.pages_page_compressed.inc();
 
@@ -330,8 +321,6 @@ static ulint fil_page_compress_for_non_full_crc32(
 	mach_write_to_2(out_buf + FIL_PAGE_DATA + FIL_PAGE_COMP_SIZE,
 			write_size);
 
-#ifdef UNIV_DEBUG
-	/* Verify */
 	ut_ad(fil_page_is_compressed(out_buf)
 	      || fil_page_is_compressed_encrypted(out_buf));
 
@@ -341,6 +330,7 @@ static ulint fil_page_compress_for_non_full_crc32(
 	ut_ad(mach_read_from_2(out_buf + FIL_PAGE_DATA + FIL_PAGE_COMP_SIZE)
 	      == write_size);
 
+#ifdef UNIV_DEBUG
 	bool is_compressed = (mach_read_from_8(out_buf + FIL_PAGE_COMP_ALGO)
 			      == (ulint) comp_algo);
 
@@ -348,19 +338,10 @@ static ulint fil_page_compress_for_non_full_crc32(
 		(mach_read_from_2(out_buf + FIL_PAGE_DATA
 				  + FIL_PAGE_ENCRYPT_COMP_ALGO)
 		 == (ulint) comp_algo);
+#endif /* UNIV_DEBUG */
 
 	ut_ad(is_compressed || is_encrypted_compressed);
 
-	/* Verify that page can be decompressed */
-	{
-		page_t tmp_buf[UNIV_PAGE_SIZE_MAX];
-		page_t page[UNIV_PAGE_SIZE_MAX];
-		memcpy(page, out_buf, srv_page_size);
-		ut_ad(fil_page_decompress(tmp_buf, page, flags));
-		ut_ad(!buf_page_is_corrupted(false, page, flags));
-	}
-#endif /* UNIV_DEBUG */
-
 	write_size+=header_len;
 
 	if (block_size <= 0) {
diff --git a/storage/innobase/fts/fts0que.cc b/storage/innobase/fts/fts0que.cc
index de592e7fb7f..9a4e7c1f486 100644
--- a/storage/innobase/fts/fts0que.cc
+++ b/storage/innobase/fts/fts0que.cc
@@ -2742,7 +2742,7 @@ fts_query_phrase_search(
 
 	/* Ignore empty strings. */
 	if (num_token > 0) {
-		fts_string_t*	token;
+		fts_string_t*	token = NULL;
 		fts_fetch_t	fetch;
 		trx_t*		trx = query->trx;
 		fts_ast_oper_t	oper = query->oper;
diff --git a/storage/innobase/handler/ha_innodb.cc b/storage/innobase/handler/ha_innodb.cc
index 3e4da9bb8b2..38429878b65 100644
--- a/storage/innobase/handler/ha_innodb.cc
+++ b/storage/innobase/handler/ha_innodb.cc
@@ -19837,7 +19837,7 @@ static TYPELIB page_compression_algorithms_typelib=
 };
 static MYSQL_SYSVAR_ENUM(compression_algorithm, innodb_compression_algorithm,
   PLUGIN_VAR_OPCMDARG,
-  "Compression algorithm used on page compression. One of: none, zlib, lz4, lzo, lzma, or bzip2",
+  "Compression algorithm used on page compression. One of: none, zlib, lz4, lzo, lzma, bzip2, or snappy",
   innodb_compression_algorithm_validate, NULL,
   /* We use here the largest number of supported compression method to
   enable all those methods that are available. Availability of compression
diff --git a/storage/innobase/handler/handler0alter.cc b/storage/innobase/handler/handler0alter.cc
index d8694da02d7..df42f20c55d 100644
--- a/storage/innobase/handler/handler0alter.cc
+++ b/storage/innobase/handler/handler0alter.cc
@@ -4758,7 +4758,11 @@ innobase_pk_order_preserved(
 		if (old_pk_column) {
 			new_field_order = lint(old_field);
 		} else if (innobase_pk_col_is_existing(new_col_no, col_map,
-						       old_n_cols)) {
+						       old_n_cols)
+			   || new_clust_index->table->persistent_autoinc
+			   == new_field + 1) {
+			/* Adding an existing column or an AUTO_INCREMENT
+			column may change the existing ordering. */
 			new_field_order = lint(old_n_uniq
 					       + existing_field_count++);
 		} else {
@@ -6919,12 +6923,6 @@ error_handling_drop_uncached_1:
 			user_table);
 		dict_index_t*	new_clust_index = dict_table_get_first_index(
 			ctx->new_table);
-		ctx->skip_pk_sort = innobase_pk_order_preserved(
-			ctx->col_map, clust_index, new_clust_index);
-
-		DBUG_EXECUTE_IF("innodb_alter_table_pk_assert_no_sort",
-			DBUG_ASSERT(ctx->skip_pk_sort););
-
 		ut_ad(!new_clust_index->is_instant());
 		/* row_merge_build_index() depends on the correct value */
 		ut_ad(new_clust_index->n_core_null_bytes
@@ -6947,6 +6945,12 @@ error_handling_drop_uncached_1:
 			}
 		}
 
+		ctx->skip_pk_sort = innobase_pk_order_preserved(
+			ctx->col_map, clust_index, new_clust_index);
+
+		DBUG_EXECUTE_IF("innodb_alter_table_pk_assert_no_sort",
+			DBUG_ASSERT(ctx->skip_pk_sort););
+
 		if (ctx->online) {
 			/* Allocate a log for online table rebuild. */
 			rw_lock_x_lock(&clust_index->lock);
diff --git a/storage/innobase/include/fil0fil.h b/storage/innobase/include/fil0fil.h
index 2cbf233a4cb..6c86deeec59 100644
--- a/storage/innobase/include/fil0fil.h
+++ b/storage/innobase/include/fil0fil.h
@@ -272,8 +272,9 @@ struct fil_space_t
 
 	/** Acquire a tablespace reference. */
 	void acquire() { n_pending_ops++; }
-	/** Release a tablespace reference. */
-	void release() { ut_ad(referenced()); n_pending_ops--; }
+	/** Release a tablespace reference.
+	@return whether this was the last reference */
+	bool release() { auto n= n_pending_ops--; ut_ad(n); return n == 1; }
 	/** @return whether references are being held */
 	bool referenced() const { return n_pending_ops; }
 
diff --git a/storage/innobase/include/page0page.h b/storage/innobase/include/page0page.h
index 0de7f50f8c2..5c3ed18a4a5 100644
--- a/storage/innobase/include/page0page.h
+++ b/storage/innobase/include/page0page.h
@@ -949,20 +949,6 @@ page_mem_alloc_free(
 				free record list */
 	ulint		need);	/*!< in: number of bytes allocated */
 /************************************************************//**
-Allocates a block of memory from the heap of an index page.
-@return pointer to start of allocated buffer, or NULL if allocation fails */
-byte*
-page_mem_alloc_heap(
-/*================*/
-	page_t*		page,	/*!< in/out: index page */
-	page_zip_des_t*	page_zip,/*!< in/out: compressed page with enough
-				space available for inserting the record,
-				or NULL */
-	ulint		need,	/*!< in: total number of bytes needed */
-	ulint*		heap_no);/*!< out: this contains the heap number
-				of the allocated record
-				if allocation succeeds */
-/************************************************************//**
 Puts a record to free list. */
 UNIV_INLINE
 void
diff --git a/storage/innobase/page/page0cur.cc b/storage/innobase/page/page0cur.cc
index c984d60a419..0586d6d8a33 100644
--- a/storage/innobase/page/page0cur.cc
+++ b/storage/innobase/page/page0cur.cc
@@ -1207,6 +1207,52 @@ page_direction_increment(
 		1U + page_header_get_field(page, PAGE_N_DIRECTION));
 }
 
+/************************************************************//**
+Allocates a block of memory from the heap of an index page.
+@return	pointer to start of allocated buffer, or NULL if allocation fails */
+static
+byte*
+page_mem_alloc_heap(
+/*================*/
+	page_t*		page,	/*!< in/out: index page */
+	page_zip_des_t*	page_zip,/*!< in/out: compressed page with enough
+				space available for inserting the record,
+				or NULL */
+	ulint		need,	/*!< in: total number of bytes needed */
+	ulint*		heap_no)/*!< out: this contains the heap number
+				of the allocated record
+				if allocation succeeds */
+{
+	byte*	block;
+	ulint	avl_space;
+
+	ut_ad(page && heap_no);
+
+	avl_space = page_get_max_insert_size(page, 1);
+
+	if (avl_space >= need) {
+		const ulint h = page_dir_get_n_heap(page);
+		if (UNIV_UNLIKELY(h >= 8191)) {
+			/* At the minimum record size of 5+2 bytes,
+			we can only reach this condition when using
+			innodb_page_size=64k. */
+			ut_ad(srv_page_size == 65536);
+			return(NULL);
+		}
+		*heap_no = h;
+
+		block = page_header_get_ptr(page, PAGE_HEAP_TOP);
+
+		page_header_set_ptr(page, page_zip, PAGE_HEAP_TOP,
+				    block + need);
+		page_dir_set_n_heap(page, page_zip, 1 + *heap_no);
+
+		return(block);
+	}
+
+	return(NULL);
+}
+
 /***********************************************************//**
 Inserts a record next to page cursor on an uncompressed page.
 Returns pointer to inserted record if succeed, i.e., enough
diff --git a/storage/innobase/page/page0page.cc b/storage/innobase/page/page0page.cc
index 2c8754a3685..86c86bd084d 100644
--- a/storage/innobase/page/page0page.cc
+++ b/storage/innobase/page/page0page.cc
@@ -251,43 +251,6 @@ page_set_autoinc(
 	}
 }
 
-/************************************************************//**
-Allocates a block of memory from the heap of an index page.
-@return pointer to start of allocated buffer, or NULL if allocation fails */
-byte*
-page_mem_alloc_heap(
-/*================*/
-	page_t*		page,	/*!< in/out: index page */
-	page_zip_des_t*	page_zip,/*!< in/out: compressed page with enough
-				space available for inserting the record,
-				or NULL */
-	ulint		need,	/*!< in: total number of bytes needed */
-	ulint*		heap_no)/*!< out: this contains the heap number
-				of the allocated record
-				if allocation succeeds */
-{
-	byte*	block;
-	ulint	avl_space;
-
-	ut_ad(page && heap_no);
-
-	avl_space = page_get_max_insert_size(page, 1);
-
-	if (avl_space >= need) {
-		block = page_header_get_ptr(page, PAGE_HEAP_TOP);
-
-		page_header_set_ptr(page, page_zip, PAGE_HEAP_TOP,
-				    block + need);
-		*heap_no = page_dir_get_n_heap(page);
-
-		page_dir_set_n_heap(page, page_zip, 1 + *heap_no);
-
-		return(block);
-	}
-
-	return(NULL);
-}
-
 /**********************************************************//**
 Writes a log record of page creation. */
 UNIV_INLINE
diff --git a/storage/maria/ma_create.c b/storage/maria/ma_create.c
index 93d65bf3a7d..b94f503641a 100644
--- a/storage/maria/ma_create.c
+++ b/storage/maria/ma_create.c
@@ -75,7 +75,7 @@ int maria_create(const char *name, enum data_file_type datafile_type,
   uint max_field_lengths, extra_header_size, column_nr;
   uint internal_table= flags & HA_CREATE_INTERNAL_TABLE;
   ulong reclength, real_reclength,min_pack_length;
-  char kfilename[FN_REFLEN], klinkname[FN_REFLEN], *klinkname_ptr;
+  char kfilename[FN_REFLEN], klinkname[FN_REFLEN], *klinkname_ptr= NullS;
   char dfilename[FN_REFLEN], dlinkname[FN_REFLEN], *dlinkname_ptr= 0;
   ulong pack_reclength;
   ulonglong tot_length,max_rows, tmp;
@@ -894,7 +894,6 @@ int maria_create(const char *name, enum data_file_type datafile_type,
     fn_format(kfilename, name, "", MARIA_NAME_IEXT,
               MY_UNPACK_FILENAME | MY_RETURN_REAL_PATH |
               (have_iext ? MY_REPLACE_EXT : MY_APPEND_EXT));
-    klinkname_ptr= NullS;
     /*
       Replace the current file.
       Don't sync dir now if the data file has the same path.
diff --git a/storage/maria/ma_loghandler.c b/storage/maria/ma_loghandler.c
index d943666065a..42755a63a03 100644
--- a/storage/maria/ma_loghandler.c
+++ b/storage/maria/ma_loghandler.c
@@ -3618,7 +3618,8 @@ my_bool translog_init_with_table(const char *directory,
   int old_log_was_recovered= 0, logs_found= 0;
   uint old_flags= flags;
   uint32 start_file_num= 1;
-  TRANSLOG_ADDRESS sure_page, last_page, last_valid_page, checkpoint_lsn;
+  TRANSLOG_ADDRESS UNINIT_VAR(sure_page), last_page, last_valid_page,
+    checkpoint_lsn;
   my_bool version_changed= 0;
   DBUG_ENTER("translog_init_with_table");
 
diff --git a/storage/myisam/mi_create.c b/storage/myisam/mi_create.c
index fd230698acc..9f17a9b2de9 100644
--- a/storage/myisam/mi_create.c
+++ b/storage/myisam/mi_create.c
@@ -46,7 +46,7 @@ int mi_create(const char *name,uint keys,MI_KEYDEF *keydefs,
   uint aligned_key_start, block_length, res;
   uint internal_table= flags & HA_CREATE_INTERNAL_TABLE;
   ulong reclength, real_reclength,min_pack_length;
-  char kfilename[FN_REFLEN],klinkname[FN_REFLEN], *klinkname_ptr;
+  char kfilename[FN_REFLEN],klinkname[FN_REFLEN], *klinkname_ptr= 0;
   char dfilename[FN_REFLEN],dlinkname[FN_REFLEN], *dlinkname_ptr= 0;
   ulong pack_reclength;
   ulonglong tot_length,max_rows, tmp;
@@ -622,7 +622,6 @@ int mi_create(const char *name,uint keys,MI_KEYDEF *keydefs,
     fn_format(kfilename, name, "", MI_NAME_IEXT,
               MY_UNPACK_FILENAME | MY_RETURN_REAL_PATH |
               (have_iext ? MY_REPLACE_EXT : MY_APPEND_EXT));
-    klinkname_ptr= 0;
     /* Replace the current file */
     create_flag=(flags & HA_CREATE_KEEP_FILES) ? 0 : MY_DELETE_OLD;
   }
diff --git a/strings/ctype-ucs2.c b/strings/ctype-ucs2.c
index 71530b0a7c1..586289c51fd 100644
--- a/strings/ctype-ucs2.c
+++ b/strings/ctype-ucs2.c
@@ -829,7 +829,7 @@ my_strtoll10_mb2(CHARSET_INFO *cs __attribute__((unused)),
                  const char *nptr, char **endptr, int *error)
 {
   const uchar *s, *end, *start, *n_end, *true_end;
-  uchar c;
+  uchar UNINIT_VAR(c);
   unsigned long i, j, k;
   ulonglong li;
   int negative;