Change logic to only allocate purge thds at startup, or
in pre-shutdown (for slow shutdown).

THD::copy_db_to(): Always return true if the output parameter
was left uninitialized. This fixes a regression that was caused
by commit 7d0d934c (MDEV-16473).

MariaDB Server 10.3 and later were unaffected by this bug
thanks to commit a7e352b5.

Possibly this bug only affects mysql_list_fields()
in the Embedded Server (libmysqld).

This bug was found by GCC 11.2.0 in CMAKE_BUILD_TYPE=RelWithDebInfo.

init_mutex_v1_t: Stop lying that the mutex parameter is const.
GCC 11.2.0 assumes that it is and could complain about any mysql_mutex_t
being uninitialized even after mysql_mutex_init() as long as
PLUGIN_PERFSCHEMA is enabled.

init_rwlock_v1_t, init_cond_v1_t: Remove untruthful const qualifiers.

Note: init_socket_v1_t is expecting that the socket fd has already
been created before PSI_SOCKET_CALL(init_socket), and therefore that
parameter really is being treated as a pointer to const.

if all options from a combination from the combinations file are already
present in the server's list of options, then don't try to run tests
in other combinations from this file.

old behavior was: if at least one option from a combination is
already present in the list...

(this was needed only for tokudb that bundled liblzma)

replaced CPACK_RPM_PACKAGE_VERSION with SERVER_VERSION.
CPACK_* variables are empty and can't be used until INCLUDE(CPack) is
called.
SERVER_VERSION is the safest option because other variables may be
overwritten from submodules

Thanks to Theodore Brockman on Zulip for noticing
on an OSX ARM64 and testing this patch.

Per https://github.com/google/cpu_features/pull/150/files
CMAKE_SYSTEM_PROCESSOR is arm64 on Apple.

Without this, compulation error:

[ 80%] Building CXX object storage/rocksdb/CMakeFiles/rocksdblib.dir/rocksdb/util/crc32c.cc.o
/mariadb/storage/rocksdb/rocksdb/util/crc32c.cc:500:18: error: use of undeclared identifier 'isSSE42'
  has_fast_crc = isSSE42();
                 ^
/mariadb/storage/rocksdb/rocksdb/util/crc32c.cc:1230:7: error: use of undeclared identifier 'isSSE42'
  if (isSSE42()) {
      ^
/mariadb/storage/rocksdb/rocksdb/util/crc32c.cc:1231:9: error: use of undeclared identifier 'isPCLMULQDQ'
    if (isPCLMULQDQ()) {
        ^

This can be reverted when the RocksDB submodule is updated.

https://github.com/facebook/rocksdb/commit/ee4bd4780b321ddb5f92a0f4eb956f2a2ebd60dc

The problem was that a PREARE followed by a non prepared statement
using DEFAULT NEXT_VALUE() could change table->next_local to point to
a not persitent memory aria. The next EXECUTE would then try to use
the wrong pointer, which could cause a crash.
Fixed by reseting the pointer to it's old value when doing EXECUTE.

Backported patch from MariaDB 10.6
The issue was that the using session_mem_used to break a test does not
guarantee where the test breaks, which gives different results
depending on the environment or how MariaDB is compield.

Buggy sepdebugcrcfix in CentOS 7 (rpm-4.11.3) does not restore
SUID bit after editing the binary. This is fixed in rpm-4.12.

Still let's not set SUID bit when installing auth_pam_tool
and use rpm spec %attr directive instead.

In a rebase of the merge, two preceding commits were accidentally reverted:
commit 112b2396 (MDEV-26308)
commit ac2857a5 (MDEV-25717)

Thanks to Daniele Sciascia for noticing this.

Changes:
- Don't include port in connection parameters with 'localhost' hostname

More info:

The hostname, if not specified or specified as '' or 'localhost', will default
to a MySQL server running on the local machine using the default for the UNIX socket.
To connect to a MySQL server on the local machine via TCP, you must specify the
loopback IP address (127.0.0.1) as the host.

To comply with what the perl module expects, we omit the port for a
host=localhost connection.

Reported issue: https://bugzilla.redhat.com/show_bug.cgi?id=1976224

FLUSH PRIVILEGES hasn't been needed for very many years.

Changes:
- Don't include port in connection parameters with 'localhost' hostname

More info:
The hostname, if not specified or specified as '' or 'localhost', will default
to a MySQL server running on the local machine using the default for the UNIX socket.
To connect to a MySQL server on the local machine via TCP, you must specify the
loopback IP address (127.0.0.1) as the host.

Reported issue: https://bugzilla.redhat.com/show_bug.cgi?id=1976224

Currently @@version_compile_machine is used by mtr
to determine if the compiled executable is 32 or 64
bits.

We extend that logic by ensuring that if the DEFAUT_MACHINE
name doesn't have "64" in its string, "-64bits" is appended
to ensure these test pass.

trx_purge_rseg_get_next_history_log(): Fix a race condition that
was introduced in commit e46f76c9
(MDEV-15912). The buffer pool page contents must not be accessed
while not holding a page latch. The page latch was released by
mtr_t::commit().

This race resulted in an ASAN heap-use-after-poison during a stress test.

To avoid potential race conditions between concurrent access to
dict_table_t::freed_indexes, let us consistently use
dict_table_t::autoinc_mutex.

dict_table_remove_from_cache_low(): To avoid extensive hold time
of table->autoinc_mutex, unconditionally free the FTS data structures.

ha_innobase::check_if_supported_inplace_alter(): Do not invoke
innobase_table_is_empty() if the tablespace has been discarded.
That is, native ALTER TABLE in InnoDB will treat an empty table
in the same way as a tablespace whose tablespace has been discarded.
(Note: ALTER TABLE...ALGORITHM=COPY will fail if the tablespace
has been discarded.)

This fixes a crash that was introduced
in commit c7559747 (MDEV-19611).