(10.0+ changes, as specified in the MDEV)

and remove unused variable (compiler warning)

The option innodb_log_compressed_pages was contributed by
Facebook to MySQL 5.6. It was disabled in the 5.6.10 GA release
due to problems that were fixed in 5.6.11, which is when the
option was enabled.

The option was set to innodb_log_compressed_pages=ON by default
(disabling the feature), because safety was considered more
important than speed. The option innodb_log_compressed_pages=OFF
can *CORRUPT* ROW_FORMAT=COMPRESSED tables on crash recovery
if the zlib deflate function is behaving differently (producing
a different amount of compressed data) from how it behaved
when the redo log records were written (prior to the crash recovery).

In MDEV-6935, the default value was changed to
innodb_log_compressed_pages=OFF. This is inherently unsafe, because
there are very many different environments where MariaDB can be
running, using different zlib versions. While zlib can decompress
data just fine, there are no guarantees that different versions will
always compress the same data to the exactly same size. To avoid
problems related to zlib upgrades or version mismatch, we must
use a safe default setting.

This will reduce the write performance for users of
ROW_FORMAT=COMPRESSED tables. If you configure
innodb_log_compressed_pages=ON, please make sure that you will
always cleanly shut down InnoDB before upgrading the server
or zlib.

The test did not handle correctly possible difference in system
timezone. The fix is to remove non-functional setting of local
time_zone and instead allow timestamp replacement to work with
any date/time

Patch submitted by Eugene Kosov <claprix@yandex.ru>,
comments added by commiter.
Signed-off-by: Vicențiu Ciorbaru <vicentiu@mariadb.org>

When using innodb_page_size=16k, InnoDB tables
that were created in MariaDB 10.1.0 to 10.1.20 with
PAGE_COMPRESSED=1 and
PAGE_COMPRESSION_LEVEL=2 or PAGE_COMPRESSION_LEVEL=3
would fail to load.

fsp_flags_is_valid(): When using innodb_page_size=16k, use a
more strict check for .ibd files, with the assumption that
nobody would try to use different-page-size files.

MDEV-10146: Wrong result (or questionable result and behavior) with aggregate function in uncorrelated SELECT subquery

When outer reference resolved in a VIEW it still should mark aggregate function resolving border.

Found by Coverity (id 971843).
Signed-off-by: Daniel Black <daniel.black@au.ibm.com>

make_lock_and_pin didn't release the lock so we should.

Found by Coverity (id 972095).

Release the lock for the error path.

Found by Coverity (id 972093).

translog_stop_writing doesn't release a lock (though
does to a DBUG_ASSERT).

Better to just release the lock.

Found by Coverity id 972092

Found by Coverity scan - id 92087

If open of the relay log failed, we got an assert in MYSQL_BIN_LOG::close
This only affected DEBUG systems

CREATE/DROP TEMPORARY TABLE are not safe to optimistically replicate in
parallel with other transactions, so they need to be marked as "ddl" in the
binlog.

This was already done for stand-alone CREATE/DROP TEMPORARY. But temporary
tables can also be created and dropped inside a BEGIN...END transaction, and
such transactions were not marked as ddl. Nor was the DROP TEMPORARY TABLE
statement emitted implicitly when a client connection is closed.

So this patch adds such ddl mark for the missing cases.

The difference to Kristian's original patch is mainly a fix in
mysql_trans_commit_alter_copy_data() to remember the unsafe_rollback_flags
over the temporary commit.

max_data_file_size is overwritten in next statement
so this assignment didn't ever get used.

Found by Coverity (ID 1409644)

CID 971836 (#1 of 1): Same on both sides (CONSTANT_EXPRESSION_RESULT)
pointless_expression: The expression val != end && val != end does not
accomplish anything because it evaluates to either of its identical
operands, val != end.

Problem was that in a circular replication setup the master remembers
position to events it has generated itself when reading from a slave.
If there are no new events in the queue from the slave, a
Gtid_list_log_event is generated to remember the last skipped event.
The problem happens if there is a network delay and we generate a
Gtid_list_log_event in the middle of the transaction, in which case there
will be an implicit comment and a new transaction with serverid=0 will be
logged.

The fix was to not generate any Gtid_list_log_events in the middle of a
transaction.

This could happen when the client connection dies while sending a progress
report packet.
Fixed by not raising any errors when sending progress packets.

MDEV-11646 main.myisam, maria.maria, main.mix2_myisam, main.myisampack, main.mrr_icp_extra fail in buildbot with valgrind (Syscall param pwrite64(buf) points to uninitialised byte(s))

If the table has a varchar column and a forced fixed for format
(as in varchar.inc), Field_varstring::store() will only store the
actual number of bytes, not padded, in the record[0].

That is, on inserts a part of record[0] can be uninitialized.

Fix: initialize record[0] when a TABLE is created, it doesn't matter
what kind of garbage can be in this unused/invisible part of the
record, as long as it's not some random memory contents
(that can contain sensitive data).

Fix the binding of databases_file. It was incorrectly mapped
to OPT_XTRA_TABLES_FILE.

Remove some unused options and variables.

tmp variable now points to str->ptr() buffer, not tmp_value buffer.
Comparing pointers otherwise can lead to false assertion errors as we
don't know where buffers are allocated in respect to each other.

cover ANSI_QUOTES and NO_BACKSLASH_ESCAPES in mysqltest

don't do backslash escapes inside backticks

Item_func_sysconst behaves as a non-constant function during prepared
statements and view creation and constant otherwise. Current condition
implied the opposite.