Now all access goes through _current_thd() and set_current_thd()
functions.

Some functions like THD::store_globals() can not fail now.

MDEV-20502 Queries against spider tables return wrong values for columns following constant declarations.

Add test cases.

fil_flush_file_spaces(): Remove the constant parameter.

buf_flush_start(), buf_flush_end(): Use static linkage.

fil_page_get_prev(), fil_page_get_next(), fil_addr_is_null(): Remove.

commit 5e7e7153 accidentally
broke the build without WSREP, by misplacing an #endif.

This is a follow-up fix to the changes that were made in MDEV-7962.

assert_trx_is_free(): Assert !is_wsrep().

trx_init(): Do not initialize trx->wsrep, because it must have been
initialized already.

trx_t::commit_in_memory(): Invoke wsrep_commit_ordered(). This call
was being skipped, because the transaction object had already been
freed to the pool.

trx_rollback_for_mysql(), innobase_commit_low(),
innobase_close_connection(): Always reset trx->wsrep.

- InnoDB gives "table is marked as crashed and should be repaired" when
table schema mismatch.

Disable IPO (interprocedural optimization, aka /GL) on Windows
on libraries, from which server.dll exports symbols -  exporting symbols
does not work for objects compiled with /GL.

Variable was not updated after initialization.

que_thr_t::magic_n: Remove. Access to freed data is best caught
by AddressSanitizer.

que_thr_t::start_running(): Replaces que_thr_move_to_run_state_for_mysql()
and que_thr_move_to_run_state(), which were identical non-inline functions.

que_thr_t::stop_no_error(): Replaces que_thr_stop_for_mysql_no_error().

que_fork_t::n_active_thrs, trx_lock_t::n_active_thrs: Make debug-only.

que_fork_t::set_active(bool active): Update n_active_thrs.

Post push fix.

when "replicate_wild_do_table" and "replicate_wild_ignore_table" filters
and changed dynamically the filter list gets cleared but the corresponding
"wild_do_table_inited" and "wild_ignore_table_inited" flags are not getting
cleared.

Fix: Clear the flags.

Adding a test case for rowid filter, the crash was fixed by MDEV-22191

KEY_MULTI_RANGE::range_flag does not have correct flag bits for
per-endpoint flags (NEAR_MIN, NEAR_MAX, NO_MIN_RANGE, NO_MAX_RANGE).
It only has bits for flags that describe both endpoints.
So
- Document this.
- Switch optimizer trace to using {start|end}_key.flag values, instead.
  This fixes the bug.
- Switch records_in_column_ranges() to doing that too. (This used to
  work, because KEY_MULTI_RANGE::range_flag had correct flag value
  for the last key component, and EITS only uses one-component
  pseudo-indexes)

trx_t::rollback(): Renamed from trx_rollback_to_savepoint().

trx_t::rollback_low(): Renamed from trx_rollback_to_savepoint_low().

fts_sql_commit(): Defined as an alias of trx_commit_for_mysql().
fts_sql_rollback(): Defined as an alias of trx_t::rollback().

fts_rename_aux_tables_to_hex_format(): Fix the error handling
that likely never worked because we failed to roll back the
first transaction.

trx_rollback_to_savepoint(): Invoke trx_t::is_wsrep().

Replace wsrep_on() with trx_t::is_wsrep() where possible.

Also, rename some functions to member functions and
remove unused DBUG_EXECUTE_IF instrumentation:

trx_t::commit(): Renamed from trx_commit().

trx_t::commit_low(): Renamed from trx_commit_low().

trx_t::commit_in_memory(): Renamed from trx_commit_in_memory().

MDEV-22337 Assertion `Alloced_length >= (str_length + length + net_le… …ngth_size(length))' failed in Binary_string::q_net_store_data on long MULTIPOLYGON query with session_track_user_variables=1 (optimized builds).

We have to reserve enough space in String to use q_something().
Also pointer calculations fixed.

…while using json_arrayagg() as a window function.

We don't support JSON_ARRAYAGG and JSON_OBJECTAGG in window functions
yet.

Problem:
=======
SET @@GLOBAL.replicate_wild_ignore_table='';
SET @@GLOBAL.replicate_wild_do_table='';

Reports following valgrind error.

Conditional jump or move depends on uninitialised value(s)
Rpl_filter::set_wild_ignore_table(char const*) (rpl_filter.cc:439)

Conditional jump or move depends on uninitialised value(s)
at 0xF60390: delete_dynamic (array.c:304)
by 0x74F3F2: Rpl_filter::set_wild_do_table(char const*) (rpl_filter.cc:421)

Analysis:
========
List of values provided for options "wild_do_table" and "wild_ignore_table" are
stored in DYNAMIC_ARRAYS.  When an empty list is provided these dynamic arrays
are not initialized.  Existing code treats empty element list as an error and
tries to clean the uninitialized list. This results in above valgrind issue.

Fix:
===
The clean up should be initiated only when there is an error while parsing the
'wild_do_table' or 'wild_ignore_table' list and the dynamic_array is in
initialized state. Otherwise for empty list it should simply return success.

During the UPDATE of PRIMARY KEY columns, we may miscalculate the
size of the clustered index record.

row_upd_clust_rec_by_insert(): Pass the total number of off-page columns,
which may include such columns that were inherited from the record
and not created as part of the UPDATE operation.

This is based on
mysql/mysql-server@490c45e8c8e07197958dbb21214fd45ed668b559
which is a follow-up to
mysql/mysql-server@1fa475b85d24de4b9ce2958c0eed738c221fc82c
which we filed and fixed as MDEV-21511.

No test case was provided by Oracle.

INSERT...SELECT reading from an InnoDB table is slow due to
creating explicit record locks. Use the sequence engine instead.

Also, remove the space before rtr_page_need_second_split
to actually make the debug injection work.

when detecting running mysqld processes to stop,
ignore processes in different namespaces.

- buf_page_get_gen() fails to set error value when it initializes the
page with redo logs.

We need to make sure that hton is not same as view_pseudo_hton
that is not NULL but not usable.

Several MYSQL_SYSVAR_STR parameters that employ both a validate
function callback fail to copy the string for saving the
validated value. The affected variables include the following:

innodb_ft_aux_table
innodb_ft_server_stopword_table
innodb_ft_user_stopword_table
innodb_buffer_pool_filename

The test case is an enhanced version of
mysql/mysql-server@0b0c30641fd66336e87394ac28587e40864f8af9
and the code changes are inspired by their fixes.

We are also importing and adjusting the test innodb_fts.stopword
to get coverage for the variable innodb_ft_user_stopword_table.

buf_dump(), buf_load(): Protect srv_buf_dump_filename with
LOCK_global_system_variables.

fts_load_user_stopword(): Minor cleanup

fts_load_stopword(): Remove the parameter global_stopword_table.

innobase_fts_load_stopword(): Protect innodb_server_stopword_table
against concurrent SET GLOBAL.

The json_arrayagg::val_str should handle NULL result.