depending on build config the error might be hidded,
in particular liblz4.so and libjemalloc.so make it to disappear,
but with -DWITH_INNODB_LZ4=NO -DWITH_JEMALLOC=NO it reappears.

no it doesn't

In commit fd9ca2a7 (MDEV-23295)
we added a debug assertion, which caught a similar bug.

prepare_inplace_alter_table_dict(): If we had promised that
ALGORITHM=INPLACE or ALGORITHM=NOCOPY is supported, we must
preserve the ROW_FORMAT.

Problem:- rpl_parallel2 was failing non-deterministically
Analysis:-
When FLUSH TABLES WITH READ LOCK is executed, it will allow all worker
threads to complete their ongoing transactions and then it will pause them.
At this state FTWRL will proceed to acquire global read lock. FTWRL first
blocks threads from starting new commits, then upgrades the lock to block
commit of existing transactions.
  Step1:
    FLUSH TABLES WITH READ LOCK - Blocks new commits
  Step2:
    * STOP SLAVE command enables 'force_abort=1' which unblocks workers,
      they continue to execute events.
    * T1: Waits in 'record_gtid' call to update 'gtid_slave_pos' table with
      its current GTID, but it is blocked becuase of Step1.
    * T2: Holds COMMIT lock and waits for T1 to commit.
  Step3:
    FLUSH TABLES WITH READ LOCK - Waiting to get BLOCK_COMMIT.
This results in deadlock. When STOP SLAVE command allows paused workers to
proceed, workers should skip the execution of all further events, similar
to 'conservative' parallel mode.
Solution:-
We will assign 1 to skip_event_group when we are aborted in do_ftwrl_wait.
rpl_parallel_entry->pause_sub_id is only reset when force_abort is off in
rpl_pause_after_ftwrl.

Problem:- rpl_parallel2 was failing non-deterministically
Analysis:-
When FLUSH TABLES WITH READ LOCK is executed, it will allow all worker
threads to complete their ongoing transactions and then it will pause them.
At this state FTWRL will proceed to acquire global read lock. FTWRL first
blocks threads from starting new commits, then upgrades the lock to block
commit of existing transactions.
  Step1:
    FLUSH TABLES WITH READ LOCK - Blocks new commits
  Step2:
    * STOP SLAVE command enables 'force_abort=1' which unblocks workers,
      they continue to execute events.
    * T1: Waits in 'record_gtid' call to update 'gtid_slave_pos' table with
      its current GTID, but it is blocked becuase of Step1.
    * T2: Holds COMMIT lock and waits for T1 to commit.
  Step3:
    FLUSH TABLES WITH READ LOCK - Waiting to get BLOCK_COMMIT.
This results in deadlock. When STOP SLAVE command allows paused workers to
proceed, workers should skip the execution of all further events, similar
to 'conservative' parallel mode.
Solution:-
We will assign 1 to skip_event_group when we are aborted in do_ftwrl_wait.
rpl_parallel_entry->pause_sub_id is only reset when force_abort is off in
rpl_pause_after_ftwrl.

/home/buildbot/buildbot/build/storage/xtradb/mtr/mtr0mtr.cc:97:37: error: invalid access to non-static data member ‘fil_space_t::latch’  of NULL object [-Werror=invalid-offsetof]

Changing that in case of *INT and hex hybrid input:
- ROUND(x,NULL) creates a column with the same type as x.
  The old code created a DOUBLE column, which was not relevant at all.
  This change simplifies the code a lot.

- ROUND(x,non_constant) creates a column of the INT, BIGINT or DECIMAL
  data type (depending on the exact type of x).
  The old code created a column of the DOUBLE data type,
  which lead to precision loss. Hence MDEV-23366.

- ROUND(bigint_30,negative_constant) creates a column of the DECIMAL(30,0)
  data type. The old code created DECIMAL(29,0), which looked strange:
  the data type promoted to a higher one, but max length reduced.
  Now the length attribute is preserved.

failed or late ER_PERIOD_FIELD_WRONG_ATTRIBUTES upon attempt to create
existing table

Analysis: Error state is not stored when field is checked in
Table_period_info::check_field()
Fix: Store error state by setting res to true.

This problem was fixed by MDEV-23368. Adding tests only.

Make sure system tables aren't open, as the test kills the server

Item_func_round::fix_arg_int() did not take into account cases
when the result of ROUND(bigint_subject,negative_precision)
could go outside of the BIGINT range. The old code only incremented
max_length, but did not extend change the data type.
Fixing to extend the data type (together with max_length increment).

The condition in Item_func_round::fix_arg_int() to decide whether:
- we can preserve the data type of args[0] versus
- the result can go outside of the args[0] data type
was wrong.

The data type of the first argument can be preserved in these cases:
- TRUNCATE(x, n)
- ROUND(x, n>=0)

Fixing the condition accordingly.

Sorry, this should have been pushed instead of
7f4c749d to 10.3.
(The push of d63631c3
prevented required an extra merge of that fix.
And that commit was merged to 10.4
da78e952.)

On MariaDB 10.4 (commit 4db4b773),
the query results would not be sorted, which creates random result
differences. Let us explicitly sort the results already in 10.3
in order to avoid future merge trouble.

On MariaDB 10.4 (commit 4db4b773),
the query results would not be sorted, which creates random result
differences. Let us explicitly sort the results already in 10.3
in order to avoid future merge trouble.

- Adding optional qualifiers to data types:
    CREATE TABLE t1 (a schema.DATE);
  Qualifiers now work only for three pre-defined schemas:

    mariadb_schema
    oracle_schema
    maxdb_schema

  These schemas are virtual (hard-coded) for now, but may turn into real
  databases on disk in the future.

- mariadb_schema.TYPE now always resolves to a true MariaDB data
  type TYPE without sql_mode specific translations.

- oracle_schema.DATE translates to MariaDB DATETIME.

- maxdb_schema.TIMESTAMP translates to MariaDB DATETIME.

- Fixing SHOW CREATE TABLE to use a qualifier for a data type TYPE
  if the current sql_mode translates TYPE to something else.

The above changes fix the reported problem, so this script:

    SET sql_mode=ORACLE;
    CREATE TABLE t2 AS SELECT mariadb_date_column FROM t1;

is now replicated as:

    SET sql_mode=ORACLE;
    CREATE TABLE t2 (mariadb_date_column mariadb_schema.DATE);

and the slave can unambiguously treat DATE as the true MariaDB DATE
without ORACLE specific translation to DATETIME.

Similar,

    SET sql_mode=MAXDB;
    CREATE TABLE t2 AS SELECT mariadb_timestamp_column FROM t1;

is now replicated as:

    SET sql_mode=MAXDB;
    CREATE TABLE t2 (mariadb_timestamp_column mariadb_schema.TIMESTAMP);

so the slave treats TIMESTAMP as the true MariaDB TIMESTAMP
without MAXDB specific translation to DATETIME.

Fixing ROUND(date,0), TRUNCATE(date,x), FLOOR(date), CEILING(date)
to return the `int(8) unsigned` data type.

Details:
1. Cleanup: moving virtual implementations
   - Type_handler_temporal_result::Item_func_int_val_fix_length_and_dec()
   - Type_handler_temporal_result::Item_func_round_fix_length_and_dec()
   to Type_handler_date_common. Other temporal data type handlers
   override these methods anyway. So they were only DATE specific.
   This change makes the code clearer.
2. Backporting DTCollation_numeric from 10.5, to reuse the code easier.
3. Adding the `preferred_attrs` argument to Item_func_round::fix_arg_int(). Now
   Type_handler_xxx::Item_func_round_val_fix_length_and_dec() work as follows:
   - The INT-alike and YEAR handlers copy preferred_attrs from args[0].
   - The DATE handler passes explicit attributes, to get `int(8) unsigned`.
   - The hex hybrid handler passes NULL, so fix_arg_int() calculates attributes.
4. Type_handler_date_common::Item_func_int_val_fix_length_and_dec()
   now sets the type handler and attributes to get `int(8) unsigned`.