The asserion failure was caused by this query

  select /*id=1*/ from t1
  where
   col= ( select /*id=2*/ from ... where corr_cond1
          union
          select /*id=4*/ from ... where corr_cond2)

Here,
- select with id=2 was correlated due to corr_cond1.
- select with id=4 was initially correlated due to corr_cond2, but then
  the optimizer optimized away the correlation, making the select with id=4
  uncorrelated.

However, since select with id=2 remained correlated, the execution had to
re-compute the whole UNION. When it tried to execute select with id=4, it
hit an assertion  (join buffer already free'd).

This is because select with id=4 has freed its execution structures after
it has been executed once. The select is uncorrelated, so it did not expect
it would need to be executed for the second time.

Fixed this by adding this logic in
st_select_lex::optimize_unflattened_subqueries():

  If a member of a UNION is correlated, mark all its members as
  correlated, so that they are prepared to be executed multiple times.

don't let Aria create a table that it cannot open

use the correct check. before invoking handler methods we
need to know that the table was opened, not only created.

Do not assume that subquery Item always present.

Removed all dependencies of command line arguments based on positions in
an array (this kind of code should never have been written).
Instead use option names, which are stable.

Reviewer: Sergei Golubchik

Use portable quoting in mtr_add_arg.

- Changed SST scripts to use /usr/bin/env bash instead of
  /bin/bash for better portability.
- Fixed use of mktemp on non-Linux platforms to produce
  temporary file instead of directory.
Reviewed-by: Jan Lindström <jan.lindstrom@mariadb.com>

(Backport Varun Gupta's patch + edit the commit comment)

Name resolution code produced errors for valid queries with window
functions (but not for queries which used aggregate functions as
window functions).

Name resolution code worked incorrectly, because window function
objects had is_window_func_sum_expr()=false. This was so, because
mark_as_window_func_sum_expr() was only called for aggregate functions
used as window functions.

The fix is to call it for any window function.

Fixed the test to execute only on linux as it depends on unportable sed.

revert 68b3fa88

accessing freed memory.
Before XMLCOL::WriteColumn() Tdbp->Clist gets assigned
a nodelist in

      Clist = RowNode->SelectNodes(g, Colname, Clist);

which is RowNode->Doc->Xop->nodesetval.

In XMLCOL::WriteColumn()

        ValNode = ColNode->SelectSingleNode(g, Xname, Vxnp);

calls LIBXMLDOC::GetNodeList() again, which frees the previous
XPath object Xop and replaces it with a new one.

In this case RowNode->Doc == ColNode->Doc, so Clist->Listp
points to a freed memory now.

fix it for Aria too

- Revert wrongly record embedded result files. These were either
  recorded with normal server (not embedded) or an embedded server
  with not default compile option. This can be seen that the committed
  result file had replication variables which should never happen.

- Reverted back change of include/is_embedded.inc. One cannot check for
  $MYSQL_EMBEDDED as this only tells if there exists an embedded
  server, not if the current server we are testing is the embedded
  server. This could easily be verified by doing
  'mtr sys_vars.sysvars_server_embedded'. This would fail with a wrong
  result instead of being marked as skipped as --embedded was not
  used.

This happens when compiled with HAVE_EMBEDDED_PRIVILEGE_CONTROL.
There is a lot of other problems with the above option that should
be fixed at some point

This avoids printing the error
"mysqld: file-key-management-filename  is not set"
which can happen if the file-key-management pluging is statically compiled

Removed the option as it safe to always create the file when we have
created the MariaDB data directories. This fixes this issue not only
for debian but for all MariaDB users.

This patch let's you specify not only user to use but also group that
MariaDB should use.

Original patch:
https://github.com/openSUSE/mysql-packaging/blob/master/patches/mysql-patches/mariadb-10.2.3-group.patch

Author:   Kristyna Streitova
Reviewer: monty@mariadb.org

The assert was caused by an error of XA transaction that had
BINLOG 'base64_string' statement.
The statement failed because of lack of checking whether the encoded
replication event was handled by the slave applier thread.
If it's not the slave applier no error should be generated, but it was
in this case, see a test added.

Fixed along with the idea borrowed the upstream to introduce a check
of which applier executes the replication event and do not
report any error if the applier is a regular server client.

Prevent the error:

setroubleshoot[23678]: SELinux is preventing /usr/libexec/mysqld from read access on the file core_pattern.

Reading of the core pattern occurs on crash as added in MDEV-15051

RHEL-7.7

$  ls -laZ /proc/sys/kernel/core_pattern
-rw-r--r--. root root system_u:object_r:usermodehelper_t:s0 /proc/sys/kernel/core_pattern

mtr is checking the wrong path for the embedded executable
on out of tree builds.

The is_embedded.inc tests are also checking the version rather
than the MTR MYSQL_EMBEDDED environment variable.

As a result, a few tests are out of date in the result recordings.

For compatibility this is under an extra option --upgrade-info

The goal here is to install a data directory with the required
info to let mysql_upgrade know that an upgrade isn't required.

MDEV-8652: Partitioned table creation problem when creating from procedure context twice in same session

The problem was solved in in MDEV-7990, this commit contains only test

This patch addresses two problems with
rpl.rpl_seconds_behind_master_spike

First, --sync_slave_with_master / select master_pos_wait
seems to have a bug where it will hang after all master
events have been executed.

This patch removes the sync_slave_with_master command from
the test, where it not required anyway as it is used to
declare explicit cleanup

Second, the test uses timestamps to ensure that the
Seconds_Behind_Master value does not point to a time too
far in the past. The checks of these timestamps were
too strict, because they could be slightly inconsistent
with the master and the SBM would be counted as invalid
when it was actually correct.

To fix this, a slight buffer was added to the check
to ensure the value is valid but still does not point
too far in the past

Reviewed By:
===========
Andrei Elkin <andrei.elkin@mariadb.com>

MDEV-25917 create table like fails if source table is partitioned and engine is myisam or aria with data directory.

Create table like removes data_file_path/index_file_path from the
thd->work_partition_info.

MDEV-24088 Assertion in InnoDB's FTS code may be triggered by a repeated words fed to simple_parser plugin

increment `position` for every word, because the plugin doesn't
(FTS API doesn't use positions that InnoDB FTS relies on)

Remove output if wsrep is not enabled.

MDEV-20516: Assertion `!lex->proc_list.first && !lex->result && !lex->param_list.elements' failed in mysql_create_view

Execution of the CREATE VIEW statement sent via binary protocol
where the flags of the COM_STMT_EXECUTE request a cursor to be opened
before running the statement results in an assert failure.

This assert fails since the data member thd->lex->result has not null
value pointing to an instance of the class Select_materialize.
The data member thd->lex->result is assigned a pointer to the class
Select_materialize in the function mysql_open_cursor() that invoked
in case the packet COM_STMT_EXECUTE requests a cursor to be opened.

After thd->lex->result is assigned a pointer to an instance of the
class Select_materialize the function mysql_create_view() is called
(indirectly via the function mysql_execute_statement()) and the assert
fails.

The assert
  DBUG_ASSERT(!lex->proc_list.first && !lex->result &&
              !lex->param_list.elements);

was added by the commit 591c06d4.
Unfortunately , the condition
  !lex->result
was specified incorrect. It was supposed that the thd->lex->result
is set only by parser on handling the clauses SELECT ... INTO
but indeed it is also set inside mysql_open_cursor() and
that fact was missed by the assert's condition.

So, the fix for this issue is to just remove the condition
  !lex->result
from the failing assert.

It's misleading to compare and write to user number of columns and fields.
Thus, it would be better to remove that check and let use see a subsequent
error message about missing or mispaced column.

row_import::match_schema(): remove misleading check

Changed the grouping and decimal separator for spanish locales as per
ICU.

Change-Id: I5d80fa59d3e66372d904e17c22c532d4dd2c565b

also fix a comment, and update a macro just in case