in trans_xa_start.

        test fixed.

In thread caching code, clear THD's warnings before reuse.

There is not current SELECT during assigning SP parameters, do not use it if current_select is empty.

fts_sync(): If the dict_table_t::to_be_dropped flag is set,
do not "goto begin_sync".

Also, clean up the way how dict_index_t::index_fts_syncing
is cleared.

It looks like this regression was introduced by merging
Oracle Bug #24938374 MYSQL CRASHED AFTER LONG WAIT ON DICT OPERATION LOCK
WHILE SYNCING FTS INDEX
https://github.com/mysql/mysql-server/commit/068f8261d4c1e134965383ff974ddf30c0758f51
from MySQL 5.6.38 into MariaDB 10.0.33, 10.1.29, 10.2.10.
The same hang is present in MySQL 5.7.20.

in trans_xa_start.

        THD.transaction.xid_state.xid.rm_error should be cleaned
        as the thread ends.

Don't call handler->position() if the last call to read a row did
not succeed.

fil_space_t::atomic_write_supported: Always set this flag for
TEMPORARY TABLESPACE and during IMPORT TABLESPACE. The page
writes during these operations are by definition not crash-safe
because they are not written to the redo log.

fil_space_t::use_doublewrite(): Determine if doublewrite should
be used.

buf_dblwr_update(): Add assertions, and let the caller check whether
doublewrite buffering is desired.

buf_flush_write_block_low(): Disable the doublewrite buffer for
the temporary tablespace and for IMPORT TABLESPACE.

fil_space_set_imported(), fil_node_open_file(), fil_space_create():
Initialize or revise the space->atomic_write_supported flag.

buf_page_io_complete(), buf_flush_write_complete(): Add the parameter
dblwr, to indicate whether doublewrite was used for writes.

buf_dblwr_sync_datafiles(): Remove an unnecessary flush of
persistent tablespaces when flushing temporary tablespaces.
(Move the call to buf_dblwr_flush_buffered_writes().)

buf_flush_init_for_writing(): Remove the parameter skip_checksum.

fsp_init_file_page_low(): Always initialize the page.

MDEV-14648 Restore fix for MySQL BUG#39053 - UNINSTALL PLUGIN does not allow the storage engine to cleanup open connections

ha_close_connection(): Do invoke the method also for plugins
for which UNINSTALL PLUGIN was deferred due to open connections.

There were some differences on MariaDB compared with MySQL.
Fix these differences.

InnoDB in Debian uses utf8mb4 as default character set since
version 10.0.20-2. This leads to major pain due to keys longer
than 767 bytes.

MariaDB 10.2 (and MySQL 5.7) introduced the setting
innodb_default_row_format that is DYNAMIC by default. These
versions also changed the default values of the parameters
innodb_large_prefix=ON and innodb_file_format=Barracuda.
This would allow longer column index prefixes to be created.
The original purpose of these parameters was to allow InnoDB
to be downgraded to MySQL 5.1, which is long out of support.

Every InnoDB version since MySQL 5.5 does support operation
with the relaxed limits.

We backport the parameter innodb_default_row_format to
MariaDB 10.1, but we will keep its default value at COMPACT.
This allows MariaDB 10.1 to be configured so that CREATE TABLE
is less likely to encounter a problem with the limitation:

	loose_innodb_large_prefix=ON
	loose_innodb_default_row_format=DYNAMIC

(Note that the setting innodb_large_prefix was deprecated in
MariaDB 10.2 and removed in MariaDB 10.3.)

The only observable difference in the behaviour with the default
settings should be that ROW_FORMAT=DYNAMIC tables can be created
both in the system tablespace and in .ibd files, no matter what
innodb_file_format has been assigned to. Unlike MariaDB 10.2,
we are not changing the default value of innodb_file_format,
so ROW_FORMAT=COMPRESSED tables cannot be created without
changing the parameter.

fix 50359719
don't rely on any specific engine checking order

Backporting from bb-10.2-compatibility to bb-10.2-ext

Version: 2018-01-26

- CREATE PACKAGE [BODY] statements are now
  entirely written to mysql.proc with type='PACKAGE' and type='PACKAGE BODY'.
- CREATE PACKAGE BODY now supports IF NOT EXISTS
- DROP PACKAGE BODY now supports IF EXISTS
- CREATE OR REPLACE PACKAGE [BODY] is now supported
- CREATE PACKAGE [BODY] now support the DEFINER clause:

    CREATE DEFINER user@host PACKAGE pkg ... END;
    CREATE DEFINER user@host PACKAGE BODY pkg ... END;

- CREATE PACKAGE [BODY] now supports SQL SECURITY and COMMENT clauses, e.g.:

    CREATE PACKAGE p1 SQL SECURITY INVOKER COMMENT "comment" AS ... END;

- Package routines are now created from the package CREATE PACKAGE BODY
  statement and don't produce individual records in mysql.proc.

- CREATE PACKAGE BODY now supports package-wide variables.
  Package variables can be read and set inside package routines.
  Package variables are stored in a separate sp_rcontext,
  which is cached in THD on the first packate routine call.

- CREATE PACKAGE BODY now supports the initialization section.

- All public routines (i.e. declared in CREATE PACKAGE)
  must have implementations in CREATE PACKAGE BODY

- Only public package routines are available outside of the package

- {CREATE|DROP} PACKAGE [BODY] now respects CREATE ROUTINE and ALTER ROUTINE
  privileges

- "GRANT EXECUTE ON PACKAGE BODY pkg" is now supported

- SHOW CREATE PACKAGE [BODY] is now supported

- SHOW PACKAGE [BODY] STATUS is now supported

- CREATE and DROP for PACKAGE [BODY] now works for non-current databases

- mysqldump now supports packages

- "SHOW {PROCEDURE|FUNCTION) CODE pkg.routine" now works for package routines

- "SHOW PACKAGE BODY CODE pkg" now works (the package initialization section)

- A new package body level MDL was added

- Recursive calls for package procedures are now possible

- Routine forward declarations in CREATE PACKATE BODY are now supported.

- Package body variables now work as SP OUT parameters

- Package body variables now work as SELECT INTO targets

- Package body variables now support ROW, %ROWTYPE, %TYPE

MDEV-15420 Wrong result for CAST from TIME or DATETIME with zero integer part and non-zero microseconds to DECIMAL(X,Y)

The loop in ull2dec() does not iterate if "from" is zero,
so to->intg got erroneously set to 0 instead of 1.
Because if this, my_decimal2seconds() wrote the fractional
part into a wrong buf[x].

Catching the special case with zero "from" and properly initialize "to"
using decimal_make_zero().

MDEV-14814: encryption.innodb_encryption-page-compression failed in buildbot with timeout on wait condition

Fix wrong wait condition.

prevents buffering in cases like

  ./mtr | tee log

fix the compilation error.
no support for plugins yet.

rocksdb and spider

Regression introducted in c2118a08 where LOCK_thd_data was moveed
to LOCK_thd_kill