Throttling only works with when creating backup.  Attempt to use it with
 --copy-back results in crash, since throttle events are not initialized.
Thus, ignore throttling unless --backup is given.

available

lz4.cmake: Check if shared or static lz4 library has LZ4_compress_default
function and if it has define HAVE_LZ4_COMPRESS_DEFAULT.

fil_compress_page: If HAVE_LZ4_COMPRESS_DEFAULT is defined use
LZ4_compress_default function for compression if not use
LZ4_compress_limitedOutput function.

Introduced a innodb-page-compression.inc file for page compression
tests that will also search .ibd file to verify that pages
are compressed (i.e. used search string is not found). Modified
page compression tests to use this file.

Note that snappy method is not included because of MDEV-12615
InnoDB page compression method snappy mostly does not compress pages
that will be fixed on different commit.

This fixes warnings that were emitted when running InnoDB test
suites on a debug server that was compiled with GCC 7.1.0 using
the flags -O3 -fsanitize=undefined.

thd_requested_durability(): XtraDB can call this with trx->mysql_thd=NULL.
Remove the function in InnoDB, because it is not used there.

calc_row_difference(): Do not call memcmp(o_ptr, NULL, 0).

innobase_index_name_is_reserved(): This can be called with
key_info=NULL, num_of_keys=0.

innobase_dropping_foreign(), innobase_check_foreigns_low(),
innobase_check_foreigns(): This can be called with
drop_fk=NULL, n_drop_fk=0.

rec_convert_dtuple_to_rec_comp(): Do not invoke memcpy(end, NULL, 0).

On 64-bit systems, the constant 1 would be 32-bit (int or unsigned)
by default. Cast the constant to ulint before shifting to avoid a
-fsanitize=undefined warning or any potential overflow.

Fix a -fsanitizer=undefined warning that trx_undo_report_row_operation()
was being passed thr=NULL when the BTR_NO_UNDO_LOG_FLAG flag was set.

trx_undo_report_row_operation(): Remove the first two parameters.
The parameter clust_entry!=NULL distinguishes inserts from updates.

This should be a non-functional change (no observable change in
behaviour; slightly smaller code).

Allocate srv_sys statically so that the desired alignment can be
guaranteed. This silences -fsanitize=undefined warnings.
There probably is no performance impact of this, because the
reason for the alignment to ensure the absence of false sharing
between counters. Even with the misalignment, each counter would
have been been aligned at 64 bits, and the counters would reside
in separate cache lines.

The parameter thr of the function btr_cur_optimistic_insert()
is not declared as nonnull, but GCC 7.1.0 with -O3 is wrongly
optimizing away the first part of the condition
UNIV_UNLIKELY(thr && thr_get_trx(thr)->fake_changes)
when the function is being called by row_merge_insert_index_tuples()
with thr==NULL.

The fake_changes is an XtraDB addition. This GCC bug only appears
to have an impact on XtraDB, not InnoDB.

We work around the problem by not attempting to dereference thr
when both BTR_NO_LOCKING_FLAG and BTR_NO_UNDO_LOG_FLAG are set
in the flags. Probably BTR_NO_LOCKING_FLAG alone should suffice.

btr_cur_optimistic_insert(), btr_cur_pessimistic_insert(),
btr_cur_pessimistic_update(): Correct comments that disagree with
usage and with nonnull attributes. No other parameter than thr can
actually be NULL.

row_ins_duplicate_error_in_clust(): Remove an unused parameter.

innobase_is_fake_change(): Unused function; remove.

ibuf_insert_low(), row_log_table_apply(), row_log_apply(),
row_undo_mod_clust_low():
Because we will be passing BTR_NO_LOCKING_FLAG | BTR_NO_UNDO_LOG_FLAG
in the flags, the trx->fake_changes flag will be treated as false,
which is the right thing to do at these low-level operations
(change buffer merge, ALTER TABLE…LOCK=NONE, or ROLLBACK).
This might be fixing actual XtraDB bugs.

Other callers that pass these two flags are also passing thr=NULL,
implying fake_changes=false. (Some callers in ROLLBACK are passing
BTR_NO_LOCKING_FLAG and a nonnull thr. In these callers, fake_changes
better be false, to avoid corruption.)

The parameter path can be passed as NULL.
This error was reported by GCC 7.1.0 when compiling
CMAKE_BUILD_TYPE=Debug with -O3.

The macro UT_LIST_INIT() zero-initializes the UT_LIST_NODE.
There is no need to call this macro on a buffer that has
already been zero-initialized by mem_zalloc() or mem_heap_zalloc()
or similar.

For some reason, the statement UT_LIST_INIT(srv_sys->tasks) in
srv_init() caused a SIGSEGV on server startup when compiling with
GCC 7.1.0 for AMD64 using -O3. The zero-initialization was attempted
by the instruction movaps %xmm0,0x50(%rax), while the proper offset
of srv_sys->tasks would seem to have been 0x48.

This is a non-functional change to make it slightly easier
to read the code. We seem to have some bugs in this
IMPORT TABLESPACE code; see MDEV-12396.

Do not silence uncertain cases, or fix any bugs.

The only functional change should be that ha_federated::extra()
is not calling DBUG_PRINT to report an unhandled case for
HA_EXTRA_PREPARE_FOR_DROP.

Do not silence uncertain cases, or fix any bugs.

The only functional change should be that ha_federated::extra()
is not calling DBUG_PRINT to report an unhandled case for
HA_EXTRA_PREPARE_FOR_DROP.

Translate "multi:" to SPH_GROUPBY_MULTIPLE.
SPH_GROUPBY_ATTRPAIR is still not supported.

Don't use instal_jar() from Use_Java.cmake -
at least in CentOS 7 (cmake 2.8.12.2) it doesn't yet support
the COMPONENT option.

remove dead code: this "return rc" could've never happened,
because reset_stmt_handle can only possibly fail if RESET_SERVER
flag is used.

But this "return rc" was confusing, it was under DBUG_ENTER (while
not being DBUG_RETURN) and it was skipping required stmt cleanup
at the end of the function.

CSV engine didn't expect CSM files to be read-only

remove useless checks
and a couple of others

bunch of bugs when external_lock() fails on unlock:
* mi_lock_database() used mi_mark_crashed() under share->intern_lock,
  but mi_mark_crashed() itself locks this mutex.
* handler::close() required table to be unlocked, but failed
  external_lock didn't count as unlock
* mysql_unlock_tables() ignored all unlock errors, but they still set
  the error status in stmt_da.

post-review fixes
* move pcre-specific variable out of mysys
* don't use current_thd
* move a commonly used macro to my_sys.h
* remove new sysvar

It was possible to construct a PCRE expression that exceeded the stack.
resulting in a crash:

With fix:

MariaDB [(none)]> SELECT 1
    -> FROM dual
    -> WHERE ('Alpha,Bravo,Charlie,Delta,Echo,Foxtrot,StrataCentral,Golf,Hotel,India,Juliet,Kilo,Lima,Mike,StrataL3,November,Oscar,StrataL2,Sand,P3,P4SwitchTest,Arsys,Poppa,ExtensionMgr,Arp,Quebec,Romeo,StrataApiV2,PtReyes,Sierra,SandAcl,Arrow,Artools,BridgeTest,Tango,SandT,PAlaska,Namespace,Agent,Qos,PatchPanel,ProjectReport,Ark,Gimp,Agent,SliceAgent,Arnet,Bgp,Ale,Tommy,Central,AsicPktTestLib,Hsc,SandL3,Abuild,Pca9555,Standby,ControllerDut,CalSys,SandLib,Sb820,PointV2,BfnLib,Evpn,BfnSdk,Sflow,ManagementActive,AutoTest,GatedTest,Bgp,Sand,xinetd,BfnAgentLib,bf-utils,Hello,BfnState,Eos,Artest,Qos,Scd,ThermoMgr,Uniform,EosUtils,Eb,FanController,Central,BfnL3,BfnL2,tcp_wrappers,Victor,Environment,Route,Failover,Whiskey,Xray,Gimp,BfnFixed,Strata,SoCal,XApi,Msrp,XpProfile,tcpdump,PatchPanel,ArosTest,FhTest,Arbus,XpAcl,MacConc,XpApi,telnet,QosTest,Alpha2,BfnVlan,Stp,VxlanControllerTest,MplsAgent,Bravo2,Lanz,BfnMbb,Intf,XCtrl,Unicast,SandTunnel,L3Unicast,Ipsec,MplsTest,Rsvp,EthIntf,StageMgr,Sol,MplsUtils,Nat,Ira,P4NamespaceDut,Counters,Charlie2,Aqlc,Mlag,Power,OpenFlow,Lag,RestApi,BfdTest,strongs,Sfa,CEosUtils,Adt746,MaintenanceMode,MlagDut,EosImage,IpEth,MultiProtocol,Launcher,Max3179,Snmp,Acl,IpEthTest,PhyEee,bf-syslibs,tacc,XpL2,p4-ar-switch,p4-bf-switch,LdpTest,BfnPhy,Mirroring,Phy6,Ptp'
    ->
    -> REGEXP '^((?!\b(Strata|StrataApi|StrataApiV2)\b).)*$');
Empty set, 1 warning (0.00 sec)

MariaDB [(none)]> show warnings;
+---------+------+---------------------------------------------------------+
| Level   | Code | Message                                                 |
+---------+------+---------------------------------------------------------+
| Warning | 1139 | Got error 'pcre_exec: Internal error (-21)' from regexp |
+---------+------+---------------------------------------------------------+

Given the OK macro used in innodb does a DBUG_RETURN(1) on expression failure
the innodb implementation has a number of errors in i_s.cc.

We introduce a new macro BREAK_IF that replaces some use of the OK macro.
Also, do some other cleanup detailed below.

When invoking Field::store() on integers, always pass the parameter
is_unsigned=true to avoid an unnecessary conversion to double.

i_s_fts_deleted_generic_fill(), i_s_fts_config_fill():
Use the BREAK_IF macro instead of OK.

i_s_fts_index_cache_fill_one_index(), i_s_fts_index_table_fill_one_index():
Add a parameter for conv_string, and let the caller allocate that buffer.

i_s_fts_index_cache_fill(): Check the return status of
i_s_fts_index_cache_fill_one_index().

i_s_fts_index_table_fill(): Check the return status of
i_s_fts_index_table_fill_one_index().

i_s_fts_index_table_fill_one_fetch(): Always let the caller invoke
i_s_fts_index_table_free_one_fetch().

i_s_innodb_buffer_page_fill(), i_s_innodb_buf_page_lru_fill():
Do release dict_sys->mutex if filling the buffers fails.

i_s_innodb_buf_page_lru_fill(): Also display the value
INFORMATION_SCHEMA.INNODB_BUFFER_PAGE.PAGE_IO_FIX='IO_PIN'
when a block is in that state. Remove the unnecessary variable 'heap'.

simple_counter::add(): Add a type cast to the os_atomic_increment_ulint()
call, because GCC would check the type compatibility even when the code
branch is not being instantiated (atomic=false). On Solaris,
os_atomic_increment_ulint() actually needs a compatible parameter type,
and an error would be emitted due to an incompatible 64-bit type,
for srv_stats.n_lock_wait_time.add(diff_time).

There is a race condition related to the variable
srv_stats.n_lock_wait_current_count, which is only
incremented and decremented by the function lock_wait_suspend_thread(),

The incrementing is protected by lock_sys->wait_mutex, but the
decrementing does not appear to be protected by anything.
This mismatch could allow the counter to be corrupted when a
transactional InnoDB table or record lock wait is terminating
roughly at the same time with the start of a wait on a
(possibly different) lock.

ib_counter_t: Remove some unused methods. Prevent instantiation for N=1.
Add an inc() method that takes a slot index as a parameter.

single_indexer_t: Remove.

simple_counter<typename Type, bool atomic=false>: A new counter wrapper.
Optionally use atomic memory operations for modifying the counter.
Aligned to the cache line size.

lsn_ctr_1_t, ulint_ctr_1_t, int64_ctr_1_t: Define as simple_counter<Type>.
These counters are either only incremented (and we do not care about
losing some increment operations), or the increment/decrement operations
are protected by some mutex.

srv_stats_t::os_log_pending_writes: Document that the number is protected
by log_sys->mutex.

srv_stats_t::n_lock_wait_current_count: Use simple_counter<ulint, true>,
that is, atomic inc() and dec() operations.

lock_wait_suspend_thread(): Release the mutexes before incrementing
the counters. Avoid acquiring the lock mutex if the lock wait has
already been resolved. Atomically increment and decrement
srv_stats.n_lock_wait_current_count.

row_insert_for_mysql(), row_update_for_mysql(),
row_update_cascade_for_mysql(): Use the inc() method with the trx->id
as the slot index. This is a non-functional change, just using
inc() instead of add(1).

buf_LRU_get_free_block(): Replace the method add(index, n) with inc().
There is no slot index in the simple_counter.

This is a backport from 10.2 where it fixes the
cmake -DWITH_ASAN test failure that was mentioned
in commit f9cc3918
(merging MDEV-12253 from 10.1 to 10.2).

fil_parse_write_crypt_data(): If the tablespace is not found,
invoke fil_space_destroy_crypt_data(&crypt_data) to properly
free the created object.

The function buf_read_page_low() invokes fil_io(), which can return
DB_ERROR when the requested page is out of bounds (such as when
restoring a buffer pool dump). The callers should be handling that.

galera_new_cluster man page and sh typo