As a follow-up to MDEV-27734 Set innodb_change_buffering=none by default
we mark the option innodb_change_buffering deprecated, to inform users
of its future removal.

Before commit 86dc7b4d (MDEV-24626)
all tablespace ID that needed recovery were known already in
recv_init_crash_recovery_spaces().

recv_sys_t::recover_deferred(): Invoke fil_names_dirty(space) on
the newly initialized tablespace. In this way, if the next log
checkpoint occurs at some LSN that is after the initialization of
the tablespace and before the last recovered LSN, a FILE_MODIFY
record will be written, so that a subsequent recovery will succeed.

The recovery was broken when
commit 0261eac5 merged the 10.5
commit f443cd11 (MDEV-27022).

Fixed inlining flags. Remove /Ob1 added by CMake for RelWithDebInfo.
(the actual compiler default is /Ob2 if optimizations are enabled)

Allow to define custom /Ob flag with new variable MSVC_INLINE, if desired

- regression got revealed while running tpcc workload.

- as part of MDEV-25919 changes logic for statistics computation was revamped.

- if the table has changed to certain threshold then table is added to
  statistics recomputation queue (dict_stats_recalc_pool_add)

- after the table is added to queue the background statistics thread is
  notified

- during revamp the condition to notify background statistics threads was
  wrongly updated to check if the queue/vector is empty when it should
  check if there is queue/vector has entries to process.

- vec.begin() == vec.end() : only when vector is empty

- also accessing these iterator outside the parallely changing vector is not
  safe

- fix now tend to notify background statistics thread if the logic adds
  an entry to the queue/vector.

srw_lock in log_sys.append_prepare() turned out to yield best throughput.
We might try a NUMA aware spin lock implementation later.

MDEV-27746 Wrong comparision of BLOB's empty preffix with non-preffixed BLOB causes rows count mismatch for clustered and secondary indexes during non-locking read

row_sel_sec_rec_is_for_clust_rec() treats empty BLOB prefix field in
secondary index as a field equal to any external BLOB field in clustered
index. Row_sel_get_clust_rec_for_mysql::operator() doesn't zerro out
clustered record pointer in row_search_mvcc(), and row_search_mvcc()
thinks that delete-marked secondary index record has visible for
"CHECK TABLE"'s read view old-versioned clustered index record, and
row_scan_index_for_mysql() counts it as a row.

The fix is to execute row_sel_sec_rec_is_for_blob() in
row_sel_sec_rec_is_for_clust_rec() if clustered field contains BLOB's
reference.

Remove unnecessary #ifdefs and dead code in Spider.
ha_spider::start_bulk_insert without uint flags is not used because
handler::ha_start_bulk_insert calls start_bulk_insert for each storage engine
with flags. Therefore, dead code and #ifdef related to
SPIDER_HANDLER_START_BULK_INSERT_HAS_FLAGS have been removed.

While building on GNU/Hurd and kfreebsd.

On the C++ standard uintptr_t can be defined in <cstdint>
ref: https://www.cplusplus.com/reference/cstdint/

Fixes: 0d44792a

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.

Fixed tpool::pread() and tpool::pwrite() to return SSIZE_T on Windows,
so that huge numbers are not converted to negatives.

Also, make sure to never attempt reading/writing more bytes than
DWORD can accomodate (4G)