It was on for alpha stages of 10.3, and now we're past that.

MDEV-12632: Source and destination overlap in memcpy, encryption.innodb-discard-import-change fails in buildbot with valgrind

Problem was that if tablespace was encrypted we try to copy
also page 0 from read buffer to write buffer that are in
that case the same memory area.

fil_iterate
	When tablespace is encrypted or compressed its
        first page (i.e. page 0) is not encrypted or
	compressed and there is no need to copy buffer.

MDEV-12632: Source and destination overlap in memcpy, encryption.innodb-discard-import-change fails in buildbot with valgrind

Problem was that if tablespace was encrypted we try to copy
also page 0 from read buffer to write buffer that are in
that case the same memory area.

fil_iterate
	When tablespace is encrypted or compressed its
        first page (i.e. page 0) is not encrypted or
	compressed and there is no need to copy buffer.

Wait until rotation has ended and shutdown before grep to make sure
that dirty pages are on datafiles.

If we use hostnames, it will fail during name resolution on UNIX systems

Also fix perfschema.hostcache_ipv6_max_con.
The test case makes use of a debug switch to execute some special code.
The code does hostname replacement. Every hostname sent during connect
phase becomes santa.claus.ipv4.example.com (or ipv6). This causes a
connection from root@localhost to fail, as root is not registered as
santa claus user. The failure is only apparent on Windows as Unix
systems make use of sockets, which bypass the name resolution check
entirely.

Fix 10.2-specific bug - copy-back is not prepared to handle system
tablespaces with absolute path.

Wait until rotation has ended and shutdown before grep to make sure
that dirty pages are on datafiles.

row_undo_step(): If innodb_fast_shutdown=3 has been requested,
abort the rollback of any non-DDL transactions. Starting with
MDEV-12323, we aborted the rollback of recovered transactions. The
transactions would be rolled back on subsequent server startup.

trx_roll_report_progress(): Renamed from trx_roll_must_shutdown(),
now that the shutdown check has been moved to the only caller.

trx_commit_low(): Allow mtr=NULL for transactions that are aborted
on rollback.

trx_rollback_finish(): Clean up aborted transactions to avoid
assertion failures and memory leaks on shutdown. This code was
previously in trx_rollback_active().

trx_rollback_to_savepoint_low(), trx_rollback_for_mysql_low():
Remove some redundant assertions.

The implementations of the convert_to_basic_const_item() virtual
function for the Item_cache classes should call cache_value() when
value_cached == NULL.

Also, shorten the test so it usually runs 2 seconds, not 3.

There was a missing argument to service_manager_extend_timeout call
and the signness of arguments did not match.

numerous fixes for CREATE ... SELECT with system versioning:
In CREATE ... SELECT the table is created based on the result set,
field properties do not count. That is
* field invisibility is *not* copied over
* AS ROW START/END is *not* copied over
* the history is *not* copied over
* system row_start/row_end fields can *not* be created from the SELECT part

[closes tempesta-tech#472]

MDEV-15391 Server crashes in JOIN::fix_all_splittings_in_plan or Assertion `join->best_read < double(1.79...e+308L)' failed

vers_setup_conds() used to AND all conditions on row_start/row_end
columns and store it either in the WHERE clause or in the ON
clause for some table. In some cases this caused ON clause
to have conditions for tables that aren't part of that ON's join.

Fixed to put a table's condition always in the ON clause of the
corresponding table.

Removed unnecessary ... `OR row_end IS NULL` clause, it's not needed
in the ON clause.

Simplified handling on PS and SP.

fix parsing of the AS OF clause

get_schema_column_record(): print 'WITHOUT SYSTEM VERSIONING` in 'EXTRA'
for such fields

--gdb now accepts an argument, it will be passed to gdb as a command.
multiple commands can be separated by a (non-standard and not escapable)
delimiter - semicolon (;).

Old usage with a bare --gdb continues to work too, of course.

disallow system versioning for tables in mysql database

use named methods instead.

the function xxx_eq(a,b) returns true if two elements
are equal and false if they are not.

strmake_buf() macro should only be used with char[] arrays,
and never with char* pointers. To distinguish between the two
we create a new variable of the same type and initialize it
using array initializer, this causes compilation failure
with pointers. The variable is unused and will be removed by the
compiler. It's enough to do this check only with gcc, so
it doesn't have to be portable.

(will be added back when it'll be used)

Wait drop table to be replicated before continuing.

The code in Type_handler_blob****::make_conversion_table_field()
erroneously assumed that row format replication uses
MYSQL_TYPE_TINYBLOB, MYSQL_TYPE_BLOB, MYSQL_TYPE_MEDIUMBLOB,
MYSQL_TYPE_LONGBLOB type codes to tranfer BLOB variations.

In fact, all BLOB variations use MYSQL_TYPE_BLOB as the type
code, while the BLOB packlength (1,2,3 or 4) it tranferred
in metadata.

The bug was introduced by  aee06808
(MDEV-9238 Wrap create_virtual_tmp_table() into a class, split into different steps)

remove dead code

If innodb_fast_shutdown<2, all transactions of active connections
will be rolled back on shutdown. This can take a long time, and
the systemd shutdown timeout should be extended during the wait.

logs_empty_and_mark_files_at_shutdown(): Extend the timeout when
waiting for other threads to complete.

This reverts commit 76ec37f5.

This behaviour change will be done separately in:
MDEV-15832 With innodb_fast_shutdown=3, skip the rollback
of connected transactions