MariaDB does support InnoDB tables with no stored columns.
(They are necessarily empty.)

On Microsoft Windows, InnoDB writes the path separator \ to the
redo log file, while on all other platforms, / is being used.

fil_name_parse(): Normalize the parsed path separators to the
native format. This allows backups or data sets to be portable
between Windows and other systems.

This is follow-up for commit 619d22dd
to fix the cmake -DWITH_EMBEDDED_SERVER build.

MariaDB before MDEV-5800 in version 10.2.2 did not support
indexed virtual columns. Non-persistent virtual columns were
hidden from storage engines. Only starting with MDEV-5800, InnoDB
would create internal metadata on virtual columns.

Similar to what was done in MDEV-18084, MDEV-18090, MDEV-18960, we adjust
one more code path for the old tables.

innobase_build_col_map(): Allocate space for virtual columns in col_map[]
but leave the entries at ULINT_UNDEFINED, noting that the virtual columns
were missing before the table was being rebuilt.

InnoDB includes 3 parsers, which use 3 lexical analyzers that
are generated with flex. Flex versions before 2.6 emitted
the keyword "register", which is deprecated in C++17.

The lexical analyzers were regenerated as follows:

for s in storage/innobase storage/xtradb
do
	(cd "$s"/pars; ./make_flex.sh)
	touch "$s"/fts/*.l
	make -C "$s"/fts -f Makefile.query
done

The MDEV-11738/MDEV-11581 fix was supposed to add the column
ROTATING_OR_FLUSHING to the INFORMATION_SCHEMA table
INNODB_TABLESPACES_ENCRYPTION, but it also added that column to
INNODB_TABLESPACES_SCRUBBING in InnoDB (not XtraDB).

The extra column was never initialized. We will remove it,
because key rotation has nothing to do with the scrubbing of
tablespace data.

It turns out, moving it to rocksdb_stress test suite is not that easy.

rec_get_offsets() was previously called in a btr_cur_optimistic_update()

* mark columns for binlog before inserting history row

Closes #822

Clarify the error message, use the wording from the manual.

Closes #870

Fix partitioning for trx_id-versioned tables.
`partition by hash`, `range` and others now work.
`partition by system_time` is forbidden.
Currently we cannot use row_start and row_end in `partition by`, because
insertion of versioned field is done by engine's handler, as well as
row_start/row_end's value set up, which is a transaction id -- so it's
also forbidden.

The drawback is that it's now impossible to use `partition by key()`
without parameters for such tables, because it references row_start and
row_end implicitly.

* add handler::vers_can_native()
* drop Table_scope_and_contents_source_st::vers_native()
* drop partition_element::find_engine_flag as unused
* forbid versioning partitioning for trx_id as not supported
* adopt vers tests for trx_id partitioning
* forbid any row_end referencing in `partition by` clauses,
  including implicit `by key()`

Fix SELECT resultset order.

MDEV-15412 For any non-existing transaction ID, AS OF provides the current table contents without a warning

Fail with error on non-existing TRX_ID.

Closes #832

When HAVE_YASSL is defined (due to cmake -DWITH_SSL=bundled
or otherwise), mysys_ssl/my_crypt.cc will #include "yassl.cc"
from the same directory.

When MariaDB 10.2 or later is compiled with GCC 8 and optimizations
are enabled, then the check
  if (iv)
in EVP_CipherInit_ex() can be wrongly optimized away.
The reason appears to be that __attribute__((nonnull)) is attached
to the variable iv, because there is a (no-op) call
memcpy(oiv, iv, ivlen=0) earlier in the code path.

It is possible that this started failing after the code was
refactored in MDEV-10332 (MariaDB 10.2.6). In MariaDB 10.1,
there is a similar memcpy() call in MyCTX_nopad::init(),
but the code appears to work fine.

The cause for this was fix MDEV-15372, which was trying to speed up
the parallel slave.

Part#1: Do not attempt the "optimization" for transactions that are not
replication slave workers.

Problem:
========
When attempting to delay a Slave attached with GTID, there appears to be an
extra delay applied initially. For example, this output reflects a Slave that is
already delayed by 43200 seconds. When switching to GTID replication,
replication is paused until SQL_Remaining_Delay counts down to 0:

CHANGE MASTER TO master_use_gtid=current_pos; CHANGE MASTER TO
MASTER_DELAY=43200;

Seconds_Behind_Master: 44847
Using_Gtid: Current_Pos
SQL_Delay: 43200
SQL_Remaining_Delay: 43089
Slave_SQL_Running_State: Waiting until MASTER_DELAY seconds after master
executed event

Analysis:
=========
When slave initiates a GTID based connection request to master, the master sends
two GTID_LIST events.  The first one is actual GTID_LIST event and the second
one is a fake GTID_LIST event. This is sent by master to provide its current
binlary log file position. The fake GTID_LIST events will have their ev->when=0.
'when' (the timestamp) is set to 0 so that slave could distinguish between real
and fake Rotate events.

On slave side when MASTER_DELAY is configured to "X" the applier will ensure
that there is a time delay of "X" seconds before the event is applied.

General behaviour of MASTER_DELAY example:-

Master
timestamp of event e1=10
timestamp of event e2=11

On slave MASTER_DELAY=5
Event e1 will be applied at = 15
e2 will be applied at =16

In bug scenario:-

On Master: With GTIDs
timestamp of event e1=10
timestamp of event e2=0

On Slave:
e1 will be applied at = 10 + 5 =15
For e2, since "e2->when=0" e2->when is set to current timestamp.
i.e since the e2->when and current timestamp on slave is the same applier waits
for additional master_delay=5 seconds. the ev->when contributes to
"rli->last_master_timestamp".

rli->last_master_timestamp= ev->when + (time_t) ev->exec_time;

Fake events should not update the "ev->when" to "current timestamp" on slave.

Fix:
===
Remove the assignment of current timestamp to "ev->when" when "ev->when=0".

This reverts commit 21b2fada
and commit 81d71ee6.

The MDEV-18464 change introduces a few data race issues. Contrary to
the documentation, the field trx_t::victim is not always being protected
by lock_sys_t::mutex and trx_t::mutex. Most importantly, it seems
that KILL QUERY could wrongly avoid acquiring both mutexes when
invoking lock_trx_handle_wait_low(), in case another thread had
already set trx->victim=true.

We also revert MDEV-12009, because it should depend on the MDEV-18464
fix being present.

1) Avoid writing of MLOG_INDEX_LOAD redo log record during inplace
alter table when the table is empty and also for spatial index.

2) Avoid creation of temporary merge file for spatial index during
index creation process.