Previously, the function could theoretically return an uninitialized
value if the system tablespace contained no data files. It should be
impossible for InnoDB to start up in such scenario.

xtrabackup_init_temp_log(): Remove a redundant variable and limit scope.

The merge omitted some InnoDB and XtraDB conflict resolutions,
most notably, failing to merge the fix of MDEV-12173.

ibuf_merge_or_delete_for_page(), lock_rec_block_validate():
Invoke fil_space_acquire_silent() instead of fil_space_acquire().
This fixes MDEV-12173.

wsrep_debug, wsrep_trx_is_aborting(): Removed unused declarations.

_fil_io(): Remove. Instead, declare default parameters for the XtraDB
fil_io().

buf_read_page_low(): Declare default parameters, and clean up some
callers.

os_aio(): Correct the macro that is defined when !UNIV_PFS_IO.

* use a longer timeout, 10ms is not always enough
* stop waiting as long as the data is read, do not unconditionally
  wait for timeout every time

mysqltest cannot free all memory on exit by design,
so there's no need to check.

mysql frees memory in mysql_end(), so enable memory-leak-on-exit check
only after it was initialized enough to use  mysql_end() - early exits
use my_end().

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

Conflicts:
	storage/innobase/lock/lock0lock.cc
	storage/xtradb/lock/lock0lock.cc
	storage/xtradb/lock/lock0wait.cc
	support-files/mysql.server.sh

Counter for select numbering made stored with the statement (before was global)
So now it does have always accurate value which does not depend on
interruption of statement prepare by errors like lack of table in
a view definition.

only do it in EXTRA_DEBUG builds

don't use internal undocumented OpenSSL functionality

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.

MDEV-13499: Backing up table that "doesn't exist in engine" cause crash in mariabackup when using encryption

Problem was that there is intentional crah when .ibd file does
not found. In mariabackup case we should avoid this crash.

When galera is used we want a stop to kill off not only the mysqld
process but the entire process group created by galera to perform
sst or wsrep_notify_cmd.`

This reverts commit 3486135b.

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

Since 736afe86 the
mysql_system_tables_data.sql only installs the anonymous
user if skip_auth_anonymous IS NULL.

Its installation is prevented by setting this to 1.

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.