There is no need for a character-set-server configuration when utf8mb4
is now the server default.

Also remove the character-set-collations as its no longer required and
the uca1400_ai_ci is now the default for all character sets that support
it. ref: MDEV-25829 / MDEV-34430.

Changing the default server character set from latin1 to utf8mb4.

Rename some threads to workaround this restrictions,
e.g "rpl_parallel_thread"->"rpl_parallel",
"slave_background" -> "slave_bg" etc.

Use SetThreadDescription/pthread_setname_np to give threads a name.

Use SetThreadDescription/pthread_setname_np to give threads a name.

Builders:
- amd64-fedora-38-last-N-failed
- amd64-debian-10-last-N-failed
erroneously execute MTR for these files:

- rpl/include/rpl_extra_col_master.test
- rpl/include.rpl_binlog_max_cache_size.test
- rpl/include.rpl_charset.test

when these files are changed by a commit.
Changing their extension from *.test to *.inc to avoid this.

my_like_range*() can create longer keys than Field::char_length().
This caused warnings during print_range().

Fix:

Suppressing warnings in print_range().

Line numbers had to be removed from the ignorelists in order to be
diffed against since locations of the same findings can differ
across runs. Therefore preprocessing has to be done on the CI findings
so that it can be compared to the ignorelist and new findings can be
outputted. However, since line numbers have to be removed, a situation
occurs where it is difficult to reference the location of findings
in code given the output of the CI job.

To lessen this pain, change the cppcheck template to include
code snippets which make it easier to reference where in the code
the finding is referring to, even in the absence of line numbers.
Ignorelisting works as before since locations of the finding may
change but not the code it is referring to.

Furthermore, due to the innate difficulty in maintaining ignorelists
across branches and triaging new findings, allow failure as to not
have constantly failing pipelines as a result of a new findings that
have not been addressed yet.

Lastly, update SAST ignorelists to match the newly refactored cppcheck
job and the current state of the codebase.

All new code of the whole pull request, including one or several
files that are either new files or modified ones, are contributed
under the BSD-new license. I am contributing on behalf of my
employer Amazon Web Services, Inc.

Rectify cases of mismatched brackets and address
possible cases of division by zero by checking if
the denominator is zero before dividing.

No functional changes were made.

All new code of the whole pull request, including one or several
files that are either new files or modified ones, are contributed
under the BSD-new license. I am contributing on behalf of my
employer Amazon Web Services, Inc.

Several variables declared in mysqld.h appear to be old system variables
that have been left over after deprecation. Delete them using IDE
refactoring to automatically search for other uses. Most cases had no
other uses in the code.

slave_allow_batching had a test that was effectively unused, as the
result was only
-ERROR HY000: Unknown system variable 'slave_allow_batching'
so that was deleted as well.

Build and test still works without issue as expected.

All new code of the whole pull request, including one or several files
that are either new files or modified ones, are contributed under the
BSD-new license. I am contributing on behalf of my employer Amazon Web
Services.

crc32_avx512(): Explicitly cast ssize_t(size) to make it clear that
we are indeed applying a negative offset to a pointer.

The issue was that when repairing an Aria table of row format PAGE and
the data file was bigger the 4G, the data file length was cut short
because of wrong parameters to MY_ALIGN().

The effect was that ALTER TABLE, OPTIMIZE TABLE or REPAIR TABLE would fail
on these tables, possibly corrupting them.
The MDEV also exposed a bug where error state was not propagated properly
to the upper level if the number of rows in the table changed.

The problem was using safe_table_name() instead of safe_table_name().str
with DBUG_PRINT

The current semi-sync binlog fail-over recovery process uses
rpl_semi_sync_slave_enabled==TRUE as its condition to truncate a
primary server’s binlog, as it is anticipating the server to re-join
a replication topology as a replica. However, for servers configured
with both rpl_semi_sync_master_enabled=1 and
rpl_semi_sync_slave_enabled=1, if a primary is just re-started (i.e.
retaining its role as master), it can truncate its binlog to drop
transactions which its replica(s) has already received and executed.
If this happens, when the replica reconnects, its gtid_slave_pos can
be ahead of the recovered primary’s gtid_binlog_pos, resulting in an
error state where the replica’s state is ahead of the primary’s.

This patch changes the condition for semi-sync recovery to truncate
the binlog to instead use the configuration variable
--init-rpl-role, when set to SLAVE. This allows for both
rpl_semi_sync_master_enabled and rpl_semi_sync_slave_enabled to be
set for a primary that is restarted, and no transactions will be
lost, so long as --init-rpl-role is not set to SLAVE.

Reviewed By:
============
Sergei Golubchik <serg@mariadb.com>

The special logic used by the memory storage engine
to keep slaves in sync with the master on a restart can
break replication. In particular, after a restart, the
master writes DELETE statements in the binlog for
each MEMORY-based table so the slave can empty its
data. If the DELETE is not executable, e.g. due to
invalid triggers, the slave will error and fail, whereas
the master will never see the problem.

Instead of DELETE statements, use TRUNCATE to
keep slaves in-sync with the master, thereby bypassing
triggers.

Reviewed By:
===========
Kristian Nielsen <knielsen@knielsen-hq.org>
Andrei Elkin <andrei.elkin@mariadb.com>

During read only mode, InnoDB doesn't allow checkpoint to happen.
So InnoDB should throw the warning when InnoDB tries to
force the checkpoint when innodb_read_only = 1 or
innodb_force_recovery = 6.

MariaDB supports a "wait-free concurrent allocator based on pinning addresses".
In `lf_pinbox_real_free()` it tries to sort the pinned addresses for better
performance to use binary search during "real free". `alloca()` was used to
allocate stack memory and copy addresses.

To prevent a stack overflow when allocating the stack memory the function checks
if there's enough stack space. However, the available stack size was calculated
inaccurately which eventually caused database crash due to stack overflow.

The crash was seen on MariaDB 10.6.11 but the same code defect exists on all
MariaDB versions.

A similar issue happened previously and the fix in fc2c1e43 was to add a
`ALLOCA_SAFETY_MARGIN` which is 8192 bytes. However, that safety margin is not
enough during high connection workloads.

MySQL also had a similar issue and the fix
https://github.com/mysql/mysql-server/commit/b086fda was to remove the use of
`alloca` and replace qsort approach by a linear scan through all pointers (pins)
owned by each thread.

This commit is mostly the same as it is the only way to solve this issue as:
1. Frame sizes in different architecture can be different.
2. Number of active (non-null) pinned addresses varies, so the frame
   size for the recursive sorting function `msort_with_tmp` is also hard
   to predict.
3. Allocating big memory blocks in stack doesn't seem to be a very good
   practice.

For further details see the mentioned commit in MySQL and the inline comments.

All new code of the whole pull request, including one or several files
that are either new files or modified ones, are contributed under the
BSD-new license. I am contributing on behalf of my employer Amazon Web
Services, Inc.

The symptoms were: take a server with no activity and a table that's
not in the buffer pool. Run a query that reads the whole table and
observe that r_engine_stats.pages_read_count shows about 2% of the table
was read. Who reads the rest?

The cause was that page prefetching done inside InnoDB was not counted.

This counts page prefetch requests made in buf_read_ahead_random() and
buf_read_ahead_linear() and makes them visible in:

- ANALYZE: r_engine_stats.pages_prefetch_read_count
- Slow Query Log: Pages_prefetched:

This patch intentionally doesn't attempt to count the time to read the
prefetched pages:
* there's no obvious place where one can do it
* prefetch reads may be done in parallel (right?), it is not clear how
  to count the time in this case.

The crash is caused by the attempt to refix the constant subquery during
pushdown from HAVING into WHERE optimization.

Every condition that is going to be pushed into WHERE clause is first
cleaned up, then refixed. Constant subqueries are not cleaned or refixed
because they will remain the same after refixing, so this complicated
procedure can be omitted for them (introduced in MDEV-21184).
Constant subqueries are marked with flag IMMUTABLE_FL, that helps to miss
the cleanup stage for them. Also they are marked as fixed, so refixing is
also not done for them.
Because of the multiple equality propagation several references to the same
constant subquery can exist in the condition that is going to be pushed
into WHERE. Before this patch, the problem appeared in the following way.
After the first reference to the constant subquery is processed, the flag
IMMUTABLE_FL for the constant subquery is disabled.
So, when the second reference to this constant subquery is processed, the
flag is already disabled and the subquery goes through the procedure of
cleaning and refixing. That causes a crash.

To solve this problem, IMMUTABLE_FL should be disabled only after all
references to the constant subquery are processed, so after the whole
condition that is going to be pushed is cleaned up and refixed.

Approved by Igor Babaev <igor@maridb.com>

Fixing applying the COLLATE clause to a parameter caused an error error:
  COLLATION '...' is not valid for CHARACTER SET 'binary'

Fix:

- Changing the collation derivation for a non-prepared Item_param
  to DERIVATION_IGNORABLE.

- Allowing to apply any COLLATE clause to expressions with DERIVATION_IGNORABLE.
  This includes:
    1. A non-prepared Item_param
    2. An explicit NULL
    3. Expressions derived from #1 and #2

  For example:
    SELECT ? COLLATE utf8mb_unicode_ci;
    SELECT NULL COLLATE utf8mb_unicode_ci;
    SELECT CONCAT(?) COLLATE utf8mb_unicode_ci;
    SELECT CONCAT(NULL) COLLATE utf8mb_unicode_ci

- Additional change: preserving the collation of an expression when
  the expression gets assigned to a PS parameter and evaluates to SQL NULL.
  Before this change, the collation of the parameter was erroneously set
  to &my_charset_binary.

- Additional change: removing the multiplication to mbmaxlen from the
  fix_char_length_ulonglong() argument, because the multiplication already
  happens inside fix_char_length_ulonglong().
  This fixes a too large column size created for a COLLATE clause.

In 10.0 there was an assert to ensure that there were semi
sync clients before removing one, but it was removed in 10.1.
This patch adds the assertion back.

The performance regression seen while loading BP is caused by the
deadlock fix given in MDEV-33543. The area of impact is wider but is
more visible when BP is being loaded initially via DMLs.  Specifically
the response time could be impacted in DML doing pessimistic operation
on index(split/merge) and the leaf pages are not found in buffer pool.
It is more likely to occur with small BP size.

The origin of the issue dates back to MDEV-30400 that introduced
btr_cur_t::search_leaf() replacing btr_cur_search_to_nth_level() for
leaf page searches. In btr_latch_prev, we use RW_NO_LATCH to get the
previous page fixed in BP without latching. When the page is not in BP,
we try to acquire and wait for S latch violating the latching order.

This deadlock was analyzed in MDEV-33543 and fixed by using the already
present wait logic in buf_page_get_gen() instead of waiting for latch.
The wait logic is inferior to usual S latch wait and is simply a
repeated sleep 100 of micro-sec (The actual sleep time could be more
depending on platforms). The bug was seen with "change-buffering" code
path and the idea was that this path should be less exercised. The
judgement was not correct and the path is actually quite frequent and
does impact performance when pages are not in BP and being loaded by
DML expanding/shrinking large data.

Fix: While trying to get a page with RW_NO_LATCH and we are attempting
"out of order" latch, return from buf_page_get_gen immediately instead
of waiting and follow the ordered latching path.

If compiled for debugging, LOCK_DURATION is also filled in.

Valgrind looks as the assertions as examining uninitalized values.

As the assertions are tested in other Debug builds we know
it isn't all invalid.

Account for Valgrind by removing the assertion under
the WITH_VALGRIND=1 compulation.