The update was lost during merge.

Before killing the server, we have to FLUSH TABLES in order to
prevent the corruption of any MyISAM system tables.

PageConverter::adjust_cluster_record(): Instead of writing
the invalid value DB_ROLL_PTR=0, write a value that indicates
a fresh insert, that is, prevents the DB_ROLL_PTR from being
dereferenced in any circumstances.

It can be argued that IMPORT TABLESPACE should actually
update the dict_index_t::trx_id to prevent older transactions
from accessing the table, similar to what I did on table
rebuild in MySQL 5.6.6 in
https://github.com/mysql/mysql-server/commit/03f81a55f221095d397c375afe8a10c8038da339

Use unsigned comparison.

Suppress some messages that are emitted rarely
(when the FIL_PAGE_FILE_FLUSH_LSN of the first page of ibdata1
does not match the latest redo log checkpoint).

Do not unwrap view references to keep table info.
(Row-IN subselect does not unwrap items so it does not need fix)

only do it in EXTRA_DEBUG builds

Whenever one copies an IO_CACHE struct, one must remember to call
setup_io_cache, if not, the IO_CACHE's current_pos and end_pos
self-references will point to the previous struct's memory, which
could go out of scope. Commit 90038693
fixes this problem in a more general fashion by removing the
self-references altogether, but for 5.5 we'll keep the old behaviour.

MDEV-15014 Assertion `m_cache_lock_status == LOCKED_NO_WAIT || m_cache_status == DISABLE_REQUEST' failed in Query_cache::free_cache on startup

The assert guards against not-locked or not-requested query cache
disabling. If during startup we disable query cache, we failed to
request disabling.

        The thd->lex->part_info should be kept intact during PS
        execution. Or the second execution gets that modified part_info.
        Let's modify ths->work_part_info instead.

Item_xml_str_func::fix_fields() used a local "String tmp" as a buffer
for args[1]->val_str(). "tmp" was freed at the end of fix_fields(),
while Items created during my_xpath_parse() still pointed to its fragments.

Adding a new member Item_xml_str_func::m_xpath_query and store the result
of args[1]->val_str() into it.

To disable debug instrumentation, save and restore the original value
of the variable DEBUG_DBUG. Assigning -d,... will enable the output of
a lot of unrelated DBUG messages to the server error log.

To disable debug instrumentation, save and restore the original value
of the variable DEBUG_DBUG. Assigning -d,... will enable the output of
a lot of unrelated DBUG messages to the server error log.

This reverts commit 3486135b.

The commit comment ended in the words: "This is needed later."
Apparently the "later" never arrived.

The patch was brought in from 5.6.39 merge and we don't need it in
MariaDB

MDEV-11539 test_if_reopen: Assertion `strcmp(share->unique_file_name,filename) || share->last_version' failed upon select from I_S

remove HA_EXTRA_PREPARE_FOR_RENAME - neither OPTIMIZE nor REPAIR need it
(was introduced in b58e7956 when replacing remove_table_from_cache()
with wait_while_table_is_used() even though remove_table_from_cache()
did not have it).

The test checks the new sys_var added to xtradb from Percona

We don't need to print an error when loading kernel32.dll. If we can't
load it we'll automatically crash. Reviewed by wlad@mariadb.com

The patches are implemented using server changes in THD. We are not
interested in having special code for certain storage engines, if
possible.

This was a leftover post 5.5->10.0 merge. It should've been deleted
there.

Main additions:

commit 543c2006a70983c2ce75024bce3679b0c20f9ae6
Author: Olivier Bertrand <bertrandop@gmail.com>
Date:   Thu Jan 4 13:51:13 2018 +0100

    - Fix MDEV-9844, MDEV-10179, MDEV-14214
     This is done by removing the tbl table type THREAD option
     that causes a multiple of sporadic bugs.
     This may be temporary depending on whether a real fix is found.
      modified:   storage/connect/mysql-test/connect/disabled.def
      modified:   storage/connect/tabtbl.cpp
      modified:   storage/connect/tabtbl.h

commit 54bc4ea024ca5fb5c137c618084d8cccfba2ee3f
Author: Olivier Bertrand <bertrandop@gmail.com>
Date:   Fri Nov 3 16:21:56 2017 +0100

    - Fix MDEV-13925: Actually this fixes SELECT queries when
      the WHERE clause have single quote.
      modified:   storage/connect/ha_connect.cc

    - Use Windows VirtualAlloc and VirtualFree for the Sarea workspace
      modified:   storage/connect/global.h
      modified:   storage/connect/ha_connect.cc
      modified:   storage/connect/jsonudf.cpp
      modified:   storage/connect/plgdbutl.cpp
      modified:   storage/connect/plugutil.cpp
      modified:   storage/connect/user_connect.cc

    - Change inihandl from c to c++.
      Because it now includes global.h that contains a bool function definition
      that make compile to fail on Linux.
      modified:   storage/connect/CMakeLists.txt
      removed:    storage/connect/inihandl.c
      added:      storage/connect/inihandl.cpp

    - Fix MDEV-13860 CONNECT engine does not build with JDBC without ODBC.
      By including Sergei's patch in connect_assisted_discovery.
      modified:   storage/connect/ha_connect.cc

commit c07064d31a4d7ee0533fec144648d93873c0dd17
Author: Olivier Bertrand <bertrandop@gmail.com>
Date:   Wed Oct 18 00:11:00 2017 +0200

    - Update version number
      modified:   storage/connect/ha_connect.cc

    - Include MONGO in all Java enabled distributions
      Mongo will be enabled only for 10.2 and 10.3
      modified:   storage/connect/CMakeLists.txt

    - Change JDBC_SUPPORT to JAVA_SUPPORT which also replaces MONGO_SUPPORT
      MONGO_SUPPORT is now just used to enable the MONGO table type
      modified:   storage/connect/filter.cpp
      modified:   storage/connect/ha_connect.cc
      modified:   storage/connect/ha_connect.h
      modified:   storage/connect/mongo.cpp
      modified:   storage/connect/mycat.cc
      modified:   storage/connect/plgdbutl.cpp
      modified:   storage/connect/tabjson.cpp
      modified:   storage/connect/tabjson.h

    - Move MakeSelector function from FILTER to mongo.cpp
      modified:   storage/connect/filter.cpp
      modified:   storage/connect/filter.h
      modified:   storage/connect/cmgoconn.cpp
      modified:   storage/connect/jmgoconn.cpp
      modified:   storage/connect/mongo.cpp

    - Do mongo_init only on first use of the MongoDB C Driver
      This will permit to delay load the mongo lib on Windows
      modified:   storage/connect/cmgoconn.cpp
      modified:   storage/connect/cmgoconn.h
      modified:   storage/connect/ha_connect.cc

    - Replace NEW_VAR by a test on MYSQL_VERSION_ID
      modified:   storage/connect/ha_connect.cc

    - Suppress enable_mongo session variable
      modified:   storage/connect/ha_connect.cc
      modified:   storage/connect/mycat.cc

    - Make some function headers identical in .h and .cc file
      (replacing const char* by PCSZ)
      modified:   storage/connect/ha_connect.cc
      modified:   storage/connect/ha_connect.h

    - Change a parameter type from uchar* to const uchar*
      (for ScanRecord and CheckRecord)
      modified:   storage/connect/ha_connect.cc
      modified:   storage/connect/ha_connect.h

    - Changes on LIKE and NOT LIKE does not fix a bug yet
      modified:   storage/connect/ha_connect.cc

    - Suppress PIVOT_SUPPORT (PIVOT type is unconditionnal)
      modified:   storage/connect/ha_connect.cc
      modified:   storage/connect/mycat.cc

    - Change the strz function from inline to static
      modified:   storage/connect/ha_connect.cc
      modified:   storage/connect/ha_connect.h

    - export the JavaConn class and the MgoColumns and IsNum functions
      modified:   storage/connect/javaconn.h
      modified:   storage/connect/json.h
      modified:   storage/connect/mongo.h

    - Fix MDEV-13924
      modified:   storage/connect/jdbconn.cpp

    - Make a temporary fix for the compiler bug in CalculateArray
      modified:   storage/connect/jsonudf.cpp
      modified:   storage/connect/tabjson.cpp

    - Typo
      modified:   storage/connect/jdbccat.h
      modified:   storage/connect/reldef.h
      modified:   storage/connect/tabext.h
      modified:   storage/connect/tabjmg.cpp
      modified:   storage/connect/tabxml.h
      modified:   storage/connect/valblk.h
      modified:   storage/connect/value.h
      modified:   storage/connect/xtable.h

    - Fix a bug in MONGO tests by changing 'MONGO' to $TYPE
      modified:   storage/connect/mysql-test/connect/t/mongo_test.inc

    - Record test results to reflect all changes
      modified:   storage/connect/mysql-test/connect/r/json_java_2.result
      modified:   storage/connect/mysql-test/connect/r/json_java_3.result
      modified:   storage/connect/mysql-test/connect/r/json_mongo_c.result
      modified:   storage/connect/mysql-test/connect/r/mongo_c.result
      modified:   storage/connect/mysql-test/connect/r/mongo_java_2.result
      modified:   storage/connect/mysql-test/connect/r/mongo_java_3.result

commit 3da90fd112e7d5ee6f0bd9c3fc3eeb4529b30e93
Author: Olivier Bertrand <bertrandop@gmail.com>
Date:   Wed Oct 11 12:21:56 2017 +0200

    Fix MDEV-13924 modified: storage/connect/jdbconn.cpp

commit 2566e67da80f291414f02c7dd6a8ca3557161d26
Author: Olivier Bertrand <bertrandop@gmail.com>
Date:   Mon Sep 11 16:38:41 2017 +0200

    Enable MONGO for the C driver. Modified: modified:   storage/connect/CMakeLists.txt

commit 27ae11db830c5d62bbf8b8b13cab976b74efe7dd
Author: Olivier Bertrand <bertrandop@gmail.com>
Date:   Tue Sep 5 19:52:04 2017 +0200

    - Update version number
      modified:   storage/connect/ha_connect.cc

    - Regard columns with binary charset as string (was binary)
      modified:   storage/connect/ha_connect.cc
      modified:   storage/connect/tabmysql.cpp
      modified:   storage/connect/tabutil.cpp

    - Support length 0 for CHAR and VARCHAR
      modified:   storage/connect/ha_connect.cc
      modified:   storage/connect/reldef.cpp
      modified:   storage/connect/value.cpp

    - Add ACCEPT option for void columns in discovery
      modified:   storage/connect/tabjson.cpp

    - Update some tests because of above change
      modified:   storage/connect/mysql-test/connect/r/json_java_2.result
      modified:   storage/connect/mysql-test/connect/r/json_java_3.result
      modified:   storage/connect/mysql-test/connect/r/json_mongo_c.result
      modified:   storage/connect/mysql-test/connect/r/mongo_c.result
      modified:   storage/connect/mysql-test/connect/r/mongo_java_2.result
      modified:   storage/connect/mysql-test/connect/r/mongo_java_3.result
      modified:   storage/connect/mysql-test/connect/r/odbc_oracle.result
      modified:   storage/connect/mysql-test/connect/r/updelx.result
      modified:   storage/connect/mysql-test/connect/t/mongo_test.inc

commit f6ee6cd1d42d861fa50fea8d9a7079347b7ddfd6
Author: Olivier Bertrand <bertrandop@gmail.com>
Date:   Sat Sep 2 16:06:10 2017 +0200

    - Fix MongoDB C Driver adding for CMAKE.
      Requires MongoDB C Driver version 1.7 now available
      modified:   storage/connect/CMakeLists.txt

    - Add more trace to tbl_thread.test (to debug failure)
      modified:   storage/connect/mysql-test/connect/r/tbl_thread.result
      modified:   storage/connect/mysql-test/connect/t/tbl_thread.test

First roll back changes, then free Items which can lead to memory freeing.

Backport 7c03edf2 from xtradb to innodb

also cover USE and other built-in commands

"tokudb_alter_table.drop_add_pk_part_104 leaves a temporary file behind"

Fixed by copying 3 lines from 10.1 to 10.0 that cleaned up the temporary
file for partitioning tables.