This bug could cause a crash for any query that used a derived table/view/CTE
whose specification was a SELECT with a GROUP BY clause and a FROM list
containing 32 or more table references.
The problem appeared only in the cases when the splitting optimization
could be applied to such derived table/view/CTE.

Also, clean up the test innodb_gis.geometry a little further.

Remove CREATE/DROP database.

Remove some unnecessary suppressions, replacements, and
SQL statements.

Populate tables via have_sequence.inc to avoid the creation of
explicit InnoDB record locks in INSERT...SELECT. This will remove
some gaps in AUTO_INCREMENT values.

After MDEV-12353, the consistency check that I originally added for
commit 1b9fe0bb
(InnoDB Plugin for MySQL 5.1) started randomly failing.

It turns out that the IMPORT TABLESPACE code was always incorrect:
it did not update the (redundantly stored) tablespace ID
in index tree root pages. It only does that for page headers
and BLOB pointers.

PageConverter::update_index_page(): Update the tablespace ID
in the BTR_SEG_TOP and BTR_SEG_LEAF of index root pages.

The problem happened in these line:

uval0= (ulonglong) (val0_negative ? -val0 : val0);
uval1= (ulonglong) (val1_negative ? -val1 : val1);

return check_integer_overflow(val0_negative ? -(longlong) res : res,
                              !val0_negative);

when unary minus was performed on -9223372036854775808.
This behavior is undefined in C/C++.

Several macros such as sint2korr() and uint4korr() are using the
arithmetic + operator while a bitwise or operator would suffice.

GCC 5 and clang 5 and later can detect patterns consisting of
bitwise or and shifts by multiples of 8 bits, such as those used
in the InnoDB function mach_read_from_4(). They actually translate
that verbose low-level code into high-level machine language
(i486 bswap instruction or fused into the Haswell movbe instruction).

We should do the same for MariaDB Server code that is outside InnoDB.

Note: The Microsoft C compiler is lacking this optimization.
There, we might consider using _byteswap_ushort(), _byteswap_ulong(),
_byteswap_uint64(). But, those would lead to unaligned reads, which are
bad for reasons stated in MDEV-20277. Besides, outside InnoDB,
most data is already being stored in the native little-endian format
of that compiler.

fil_delete_tablespace(): Remove the unused parameter drop_ahi,
and add the parameter if_exists=false. We want to suppress
error messages if we know that the tablespace has been discarded.

dict_table_rename_in_cache(): Pass the new parameter to
fil_delete_tablespace(), that is, do not complain about
missing tablespace if the tablespace has been discarded.

row_make_new_pathname(): Declare as static.

row_drop_table_for_mysql(): Tolerate !table->data_dir_path
when the tablespace has been discarded.

row_rename_table_for_mysql(): Skip part of the RENAME TABLE
when fil_space_get_first_path() returns NULL.

buf_pool_resize(): Simplify the fault injection
for innodb.buf_pool_resize_oom.

innodb.buf_pool_resize_oom: Use a small buffer pool.

innodb.innodb_buffer_pool_load_now: Make use of the sequence engine,
to avoid creating explicit InnoDB record locks. Clean up the
accesses to information_schema.innodb_buffer_page_lru.

Tests fixed.
MBR::Within() function fixed.

- This issue is caused by MDEV-19176
(bba59abb).
- Problem is that there is miscalculation of available memory during
recovery if innodb_buffer_pool_instances > 1.
- Ignore the buffer pool instance while calculating available_memory
- Removed recv_n_pool_free_frames variable and use buf_pool_get_n_pages()
instead.

Temporary tables are typically short-lived, and temporary tables
are assumed to be accessed only by the thread that is handling
the owning connection. Hence, they must not be subject to
defragmenting.

ha_innobase::optimize(): Do not add temporary tables to
the defragment_table() queue.

AUTO_INCREMENT values are nondeterministic after crash recovery.
While MDEV-6076 guarantees that the AUTO_INCREMENT values of committed
transactions will not roll back, it is possible that the AUTO_INCREMENT
values will be durably incremented for incomplete transactions. So
changing the test case to avoid showing the result of AUTO_INCREMENT value.

Error message now shows the whole value.

Rows_log_event::change_to_flashback_event(): Reduce the scope
of the variable swap_buff2, and do not duplicate conditions.

GCC 9.3.0 flagged the -Wmaybe-uninitialized when compiling the
10.5 branch using cmake -DWITH_ASAN=ON -DCMAKE_CXX_FLAGS=-O2

Function os_file_get_last_error_low returns error number +
OS_FILE_ERROR_MAX (which is currently set to 200) for unknown numbers to
this program.

This should fix the following failure:

+ Warnings:
+ Warning       1639    debug sync point wait timed out

to work better for CPUs with more than 2000 bogomips.
old behavior is preserved if less than 2500 bogomips.

see e.g. `add_to_status()`

myrg_open(): Reduce the scope of the variable 'end' and
simplify the code.

For some reason, I got no warning for this code in the 10.2
branch, only 10.3 or later.

The ENGINE=MERGE is covered by the tests main.merge, main.merge_debug,
and main.merge-big.

Problem:
=======
When we upgrade from "mysql" to "mariadb" if slave is using repositories as
tables their data is completely ignored and no warning is issued in error log.

Fix:
===
"mysql_upgrade" test should check for the presence of data in
"mysql.slave_master_info" and "mysql.slave_relay_log_info" tables. When tables
have some data the upgrade script should report a warning which hints users
that the data in repository tables will be ignored.

_ma_fetch_keypage(): Correct an assertion that used to always hold.
Thanks to clang -Wint-in-bool-context for flagging this.

double_to_datetime_with_warn(): Suppress -Wimplicit-int-float-conversion
by adding a cast. LONGLONG_MAX converted to double will actually be
LONGLONG_MAX+1.

All tablespace metadata is buffered in fil_system. There is a LRU
mechanism, but that only controls the opening and closing of
fil_node_t::handle.

It is much more efficient and less error-prone to access data file names
by looking up the fil_space_t object rather than by essentially joining
each row with an access to SYS_DATAFILES via the InnoDB internal SQL parser.

dict_get_first_path(): Declare static. The function may only be needed
when loading or updating the data dictionary. Also, change a condition
in order to avoid a bogus GCC 10 -Wstringop-overflow warning for
mem_strdupl() about len==ULINT_UNDEFINED.

i_s_sys_tablespaces_fill_table(): Do not access other InnoDB internal
dictionary tables than SYS_TABLESPACES.

This fixes GCC 10.0.1 -Wstringop-truncation and some typos.

actually, page_zip_verify_checksum() generally allows all-zeroes
checksums because our CRC32 checksum is something like
crc_1 ^ crc_2 ^ crc_3

Also, all zeroes page is considered correct.

As a side effect fix nasty reinterpret_cast<> UB

Also, since c0f47a4a innodb_checksum_algorithm=full_crc32
exists which computes CRC32 in one go (without bitwise arithmetic)