trx_purge_stop(): Release purge_sys->latch before attempting to
wake up the purge threads, so that they can actually wake up.
This is a regression of commit a13a636c
which attempted to fix MDEV-11802 by ensuring that srv_purge_wakeup()
will actually wait until all purge threads wake up.
Due to the purge_sys->latch, the threads might never wake up,
because some purge threads could end up waiting for purge_sys->latch
in trx_undo_prev_version_build() while holding dict_operation_lock
in shared mode. This in turn would block any DDL operations, the
InnoDB master thread, and InnoDB shutdown.

Down-scale the test by a factor of 2.

Backport the fix from the upstream and add our testcase.
Backported cset:
commit 997a979bf5e2f75ab88781d9d3fd22dddc1fc21f
Author: Manuel Ung <mung@fb.com>
Date:   Thu Feb 15 08:38:12 2018 -0800

    Fix crashes in autoincrement code paths

    Summary:
    There are two issues related to autoincrement that can lead to crashes:

    1. The max value for double/float type for autoincrement was not implemented in MyRocks, and can lead to assertions. The fix is to add them in.
    2. If we try to set auto_increment via alter table on a table without an auto_increment column defined, we segfault because there is no index from which to read the last value. The fix is to perform a check to see if autoincrement exists before reading from index (similar to code ha_rocksdb::open).

    Fixes https://github.com/facebook/mysql-5.6/issues/792
    Closes https://github.com/facebook/mysql-5.6/pull/794

    Differential Revision: D6995096

    Pulled By: lth

    fbshipit-source-id: 1130ce1

            failure upon SELECT with impossible condition

The problem appears because of a wrong implementation of the
Item_func_in::build_clone() method. It didn't clone 'array' and 'cmp_fields'
fields for the cloned IN predicate and this could cause crashes.
The Item_func_in::fix_length_and_dec() method was refactored and a new method
named Item_func_in::create_array() was created. It allowed to create 'array'
for cloned IN predicates in a proper way.

            work in the IN subqueries

The pushdown into the materialized derived table/view wasn't done because
optimize() for the derived was called before any conditions that can
be pushed down were extracted. So optimize() in
convert_join_subqueries_to_semijoins() method is called too early and is
unnecessary. The second optimize() call in mysql_handle_single_derived()
is enough.

In InnoDB, CREATE TEMPORARY TABLE does not allow FULLTEXT INDEX.
Replace a condition with a debug assertion, and add a test.

Problem:

Fix for Bug #21348684 (#Rb9581) introduced a conditional debug execute
'buf_pool_resize_chunk_null', which causes new chunks memory for 2nd
buffer pool instance is freed.

Buffer pool resize function removes all old chunks entry from
'buf_chunk_map_reg' and add new chunks entry into it. But when
'buf_pool_resize_chunk_null' is set true, 2nd buffer pool
instance's chunk entries are not added into 'buf_chunk_map_reg'.
When purge thread tries to access that buffer chunk, it leads to
debug assertion.

Fix:

Added old chunk entries into 'buf_chunk_map_reg' for 2nd buffer pool
instance when 'buf_pool_resize_chunk_null' debug condition is set to true.

Reviewed by: Jimmy <Jimmy.Yang@oracle.com>
RB: 18664

PROBLEM

Issue found during ntest run is a regression of  Bug #27141613. The
issue is basically when index is being freed due to an error during its
creation,when the index isn't added to dictionary cache its field
columns are not set, the derefrencing of null col pointer during the
clean of index from the virtual column's leads to a crash.

NOTE: Also test i_innodb.virtual_debug was failing on 32k page size and
above for the newly added scenario. Fixed that.

FIX

Added a check that if only the index is cached , the virtual index
freeing from the virtual cols index list is performed.

Reviewed by: Satya Bodapati<satya.bodapati@oracle.com>
RB: 18670

PROBLEM
=======
When add of virtual index fails with DB_TOO_BIG_RECORD , the virtual
index being freed isn't removed from the list of indexes a virtual
column(which is part of the index). This while the undo log is read
could fetch a wrong value during rollback and cause the assertion
reported in the bug particularly.

FIX
===
Added a function that is called when the virtual index being freed would
allow the index be removed from the index list of virtual column which
was a field of that index.

Reviwed By: Jimmy Yang<Jimmy.Yang@oracle.com>
RB: 18528

PROBLEM
-------

Whenever an fts table is created it registers itself in a queue which
is operated by a background thread whose job is to optimize the
fts tables in background. Additionally we place these fts tables in
non-LRU list so that they cannot be evicted from cache. But in the
scenario when a node is brought up which is already having fts
tables ,we first try to load the fts tables in dictionary ,but we skip
the part where it is added in background queue and in non-LRU list because
the background thread is not yet created,so these tables are loaded
but they can be evicted from the cache. Now coming to the deadlock scenario

1. A Server background thread is trying to evict a table from the cache
    because the cache is full,so it scans the LRU list for the tables it can
    evict.It finds the fts table (because of the reason explained above)
    can be evicted and it takes the dict_sys->mutex (this is a system wide mutex)
    submits a request to  the background thread to remove this table from queue
    and waits it to be completed.

2.  In the mean time fts_optimize_thread() is processing another job
    in the queue and needs dict_sys->mutex for a small amount of time,
    but it cannot get it because it is blocked by the first background thread.

So Thread 1 is waiting for its job to be completed by Thread 2,whereas Thread 2
is waiting for dict_sys->mutex held by thread 1 ,causing the deadlock.

FIX

Problem:

when incorrect value is assigned to innodb_data_file_path or
innodb_temp_data_file_path parameter, Innodb returns error and logs error
message in mysqlds.err file but there is no information in error message about
the parameter which causes Innodb initialization is failed.

Fix:

Added error message with parameter name and value, which causes Innodb
initialization is failed.

Reviewed by: Jimmy <Jimmy.Yang@oracle.com>
RB: 18206

Note: it does not appear to cover the bug fix! The test
will pass even if the Oracle Bug #26731689 fix is reverted.

Problem:

During ALTER, when filling stored column info, wrong column number is used.
This is because we ignored virtual column when iterating over columns in
table and lead to debug assertion.

Fix:

In InnoDB table cache object, vcols are on stored on one list, stored and
normal columns are stored in another list.
When looking for stored column, ignore the virtual columns to get the right
column number of stored column.

Reviewed by: Thiru <thirunarayanan.balathandayuth@oracle.com>,
             Satya <satya.bodapati@oracle.com>
RB: 17939

This is the MariaDB equivalent of fixing the MySQL 5.7 regression
Bug #26935001 ALTER TABLE AUTO_INCREMENT TRIES TO READ
INDEX FROM DISCARDED TABLESPACE

Oracle did not publish a test case, but it is easy to guess
based on the commit message. The MariaDB code is different
due to MDEV-6076 implementing persistent AUTO_INCREMENT.

commit_set_autoinc(): Report ER_TABLESPACE_DISCARDED if the
tablespace is missing.

prepare_inplace_alter_table_dict(): Avoid accessing a discarded
tablespace. (This avoids generating warnings in fil_space_acquire().)

Problem:
When FTS index is added into a table which doesn't have 'FTS_DOC_ID'
column, Innodb rebuilds table to add column 'FTS_DOC_ID'. when this FTS
index is dropped from this table. Innodb doesn't not rebuild table to
remove 'FTS_DOC_ID' column and deletes FTS index auxiliary tables.
But it doesn't delete FTS common auxiliary tables.
Later when the database having this table is renamed, FTS auxiliary
tables are not renamed because table's flags2 (dict_table_t.flags2)
has been resetted for DICT_TF2_FTS flag during FTS index drop operation.
Now when we drop old database, it leads to an assert.

Fix:
During renaming of FTS auxiliary tables, ORed a condition to check if
table has DICT_TF2_FTS_HAS_DOC_ID flag set.

RB: 18769
Reviewed by : Jimmy.Yang@oracle.com

Problem:
=======
Multiple insert statement in table contains FULLTEXT KEY and a
FTS_DOC_ID column aborts the server if the FTS_DOC_ID exceeds
FTS_DOC_ID_MAX_STEP.

Solution:
========
Remove the exception for first committed insert statement.

Reviewed-by: Jimmy Yang<jimmy.yang@oracle.com>
RB: 18023

When Oracle fixed MDEV-13899 in their own way, they moved the
condition to the only caller of PageConverter::update_records().
Thus, the merge of 5.6.40 into MariaDB added a redundant condition.

PageConverter::update_records(): Move the page_is_leaf() condition
to the only caller, PageConverter::update_index_page().

Enable the test as the cause of the failure has been fixed

The issue here is that the window function execution is not called for the correct join tab, when we have GROUP BY
where we create extra temporary tables then we need to call window function execution for the last join tab. For doing
so the current code does not take into account the JOIN::aggr_tables.
Fixed by introducing a new function JOIN::total_join_tab_cnt that takes in account the temporary tables also.

It produced warnings due to perl code printing \r\n into the text
file which is then used by LOAD DATA INFILE.

Table name may be passed either as "./db/table" or as ".\\db\\table".

QUERY_DML_NO_SELECT flag added.

QUERY_DML_NO_SELECT flag added.

QUERY_DML_NO_SELECT flag added.

MDEV-15746 ASAN heap-use-after-free in Item_change_list::rollback_item_tree_changes on ALTER executed as PS

don't try to convert a default value string from a user character set
into a column character set, if this particular default value string did
not came from the user at all (that is, if it's an ALTER TABLE and the
default value string is the *old* default value of the unaltered
column).

This used to crash, because old defaults are allocated on the old
table's memroot, which is freed mid-ALTER when the old table is closed.
So thd->rollback_item_tree_changes() at the end of the ALTER was writing
into the freed memory.

table.cc:
  virtual columns must be computed for INSERT, if they're part
  of the partitioning expression.

this change broke gcol.gcol_partition_innodb.
fix CHECK TABLE for partitioned tables and vcols.

sql_partition.cc:
  mark prerequisite base columns in full_part_field_set
ha_partition.cc
  initialize vcol_set accordingly

This previously unreported warning comes from casting size_t to ulong
in sql_hset.h in Hash_Set::at().

Change my_hash_element to accept size_t index parameter.