The only InnoDB change between MySQL 5.7.30 and MySQL 5.7.31
that is applicable to MariaDB Server was applied in
commit 8d061996 (MDEV-23161).

The only InnoDB changes between Percona XtraDB Server 5.6.47-87.0
and 5.6.48-88.0 are related to InnoDB changes between MySQL 5.6.47
and MySQL 5.6.48, which we had already applied.

There were no InnoDB changes between MySQL 5.6.48 and MySQL 5.6.49.

This issue was originally reported by Fungo Wang, along with a fix, as
MySQL Bug #98990.

His suggested fix was applied as part of
mysql/mysql-server@a003fc373d1adb3ccea353b5d7d83f6c4c552383
and released in MySQL 5.7.31.

i_s_metrics_fill(): Add the missing call to Field::set_notnull(),
and simplify some code.

- i_s_fts_index_cache_fill() should take shared lock of fts cache
before accessing index cache to avoid reading stale data.

- Problem is that test case creates iblogfile* files. So existing
ibdata pages could point to future LSN. Fix is that taking the
backup of data before iblogfile* creation and apply it before
exiting the test case.

MDEV-22890 DEADLOCK of threads detected: row0sel.cc S-LOCK / btr0cur.cc S-LOCK / row0quiesce.cc X-LOCK

Problem:
=======
- Read operations are always allowed to hold a secondary index leaf
latch and then look up the corresponding clustered index record.
Flush table operation acquires secondary index latch while holding
a clustered index latch. It leads to deadlock violation.

Fix:
====
- Flush table operation should acquire secondary index before taking
clustered index to avoid deadlock violation with select operation.

Only install wsrep scripts and links if WSREP_ON is actually set

MDEV-22463: Element_type &Bounds_checked_array<Item *>::operator[](size_t) [Element_type = Item *]: Assertion `n < m_size' failed.

Allocate space for fields inside the window function (arguments, PARTITION BY and ORDER BY clause)
in the ref pointer array. All fields inside the window function are part of the temporary
table that is required for the window function computation.

MDEV-22058: Assertion `!is_set() || (m_status == DA_OK_BULK && is_bulk_op())' failed in Diagnostics_area::set_ok_status

Error state is not stored in check_and_do_in_subquery_rewrites() when there is
illegal combination of optimizer switches. So all the functions eventually
return false. Thus the assetion failure.

The client can only find out if the server has disconnected when it tries to
read or send something. If the server gets disconnected before
send_client_reply_packet(), the client will try sending authentication
information but it will fail. But, if the client is fast enough to send
autentication information before disconnecting, it will notice that when
reading the ok packet. So the client can fail on read or on write.
It is unpredictable because, the process are unsynchronized and this
could happen in any order.

Reject queries that have aggregate functions with UNION as these
are not allowed by standard.

When setting the PLUGIN_AUTH_PAM variable, mark it as a "CACHE" variable
so it can be overridden by the user.

Pass the unsigned flag from the Item_sum to the window function

failed in Diagnostics_area::set_ok_status on FUNCTION replace

When there is REPLACE in the statement, sp_drop_routine_internal() returns
0 (SP_OK) on success which is then assigned to ret. So ret becomes false
and the error state is lost. The expression inside DBUG_ASSERT()
evaluates to false and thus the assertion failure.

While trying to detect datadir, take into account that one can use
Windows service name as section name in options file, for Windows service.

The historical obscurity is being used by WAMP installations.

MDEV-22390: Assertion `m_next_rec_ptr >= m_rawmem' failed in Filesort_buffer::spaceleft | SIGSEGV in __memmove_avx_unaligned_erms from my_b_write

Make sure that the sort_buffer that is allocated has atleast space for MERGEBUFF2 keys.
The issue here was that the record length is quite high and sort buffer size is very small,
due to which we end up with zero number of keys in the sort buffer. The Sort_param::max_keys_per_buffer
was zero in such a case, due to which we were flushing empty sort_buffer to the disk.

accept might return an error, including SOCKET_EAGAIN/
SOCKET_EINTR. The caller, usually handle_connections_sockets
can these however and invalid file descriptor isn't something
to call fcntl on.

Thanks to Etienne Guesnet (ATOS) for diagnosis,
sample patch description and testing.

This reverts commit e0793d38.

In idiomatic C++, accessor functions should not discard qualifiers.

- service not using "--defaults-file" can have any name not just "MySQL"
- service with "--defaults-file", without datadir in them
use default datadir (install_root\data)

MemorySanitizer (clang -fsanitize=memory) requires that all code
be compiled with instrumentation enabled. The only exception is the
C runtime library. Failure to use instrumented libraries will cause
bogus messages about memory being uninitialized.

In WITH_MSAN builds, we must avoid calling getservbyname(),
because even though it is a standard library function, it is
not instrumented, not even in clang 10.

Note: Before MariaDB Server 10.5, ./mtr will typically fail
due to the old PCRE library, which was updated in MDEV-14024.

The following cmake options were tested on 10.5
in commit 94d0bb4d:

cmake \
-DCMAKE_C_FLAGS='-march=native -O2' \
-DCMAKE_CXX_FLAGS='-stdlib=libc++ -march=native -O2' \
-DWITH_EMBEDDED_SERVER=OFF -DWITH_UNIT_TESTS=OFF -DCMAKE_BUILD_TYPE=Debug \
-DWITH_INNODB_{BZIP2,LZ4,LZMA,LZO,SNAPPY}=OFF \
-DPLUGIN_{ARCHIVE,TOKUDB,MROONGA,OQGRAPH,ROCKSDB,CONNECT,SPIDER}=NO \
-DWITH_SAFEMALLOC=OFF \
-DWITH_{ZLIB,SSL,PCRE}=bundled \
-DHAVE_LIBAIO_H=0 \
-DWITH_MSAN=ON

MEM_MAKE_DEFINED(): An alias for VALGRIND_MAKE_MEM_DEFINED()
and __msan_unpoison().

MEM_GET_VBITS(), MEM_SET_VBITS(): Aliases for
VALGRIND_GET_VBITS(), VALGRIND_SET_VBITS(), __msan_copy_shadow().

InnoDB: Replace the UNIV_MEM_ macros with corresponding MEM_ macros.

ut_crc32_8_hw(), ut_crc32_64_low_hw(): Use the compiler built-in
functions instead of inline assembler when building WITH_MSAN.
This will require at least -msse4.2 when building for IA-32 or AMD64.
The inline assembler would not be instrumented, and would thus cause
bogus failures.

mariabackup tries to allocate a buffer of page_size*page_size/4 size.
for 64k page it means 1Gb, which doesn't work very well on 32-bit builders.

Skip the 64k page test on 32bit.

and remove it on error

Disable existing non-empty datadir for mysql_install_db.exe

The issue here is for a DEPENDENT subquery that has an aggregate function in the ORDER BY clause,
is wrapped inside an Item_aggregate_ref. For computation of ORDER BY we need to refer to the
temp table field corresponding to this item. But in the function make_sortorder, we were
explicitly casting Item_aggrgate_ref to Item_sum, which leads to us not getting the temp
table field corresponding to the item.

MDEV-23003 INFORMATION_SCHEMA.INNODB_TABLESPACES_ENCRYPTION requires SUPER instead PROCESS privilege

Fix a typo in a source code. Now real required privileges corresponds
to a ones mentions in documentation.

Documentation states that this table requires PROCESS privilege:
https://mariadb.com/kb/en/information-schema-innodb_tablespaces_encryption-table/

Window function is not allowed as arguments to window functions according to the standard.

This function is very common in a debug build. I can even see it in
profiler.

This patch reduces execution time of fil_validate() from
8948ns
8367ns
8650ns
8906ns
8448ns

to
260ns
232ns
403ns
275ns
169ns
in my environment.

The trick is a faster fil_space_t iteration. Hash table
is typically initialized with a size of 50,000. And looping through
it is slow. Slower, than iterating an exact amount of fil_space_t
which is typically less than ten.

Only debug builds are affected.

The issue here was that the left expr and right expr of the ANY subquery
had different character sets, so we were converting the left expr to utf8 character set.
So when this conversion was happening we were actually converting the item inside the cache,
it looked like <cache>(convert(t1.l1 using utf8)), which is incorrect.
To fix this problem we are going to store the reference of the left expr and convert that
to utf8 character set, it would look like convert(<cache>(`test`.`t1`.`l1`) using utf8)