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.

Problem was two race condtion in Aria page cache:
- find_block() didn't inform free_block() that it had released requests
- free_block() didn't handle pinned blocks, which could happen if
  free_block() was called as part of flush. This is fixed by not freeing
  blocks that are pinned.  This is safe as when maria_close() is called
  when last thread is using a table, there can be no pinned blocks. For
  other flush calls it's safe to ignore pinned blocks.

- Changed to 'strict'
- Fixed scope of variables
- Made timing smaller for of repair, check, flush and alter to get them to
  trigger earlier

In MariaDB Server before 10.2, InnoDB will not be shut down properly
if startup fails. So, Valgrind failures are to be expected.
Disable the test under Valgrind. In 10.2, it should pass with Valgrind.

This patch corrects the fix for the bug mdev-10693.
It is critical for the function get_best_combination() not to call
create_ref_for_key() for constant tables.
This bug could manifest itself only in multi-table subqueries where
one of the tables is accessed by a constant primary key.

otherwise make didn't know it needs to regenerate lex_hash.h
when gen_lex_hash (that is sql_yacc.h, that is sql_yacc.yy) changes.

/home/travis/build/MariaDB/server/extra/mysqld_safe_helper.c:62:21: warning: too many arguments in call to 'do_usage'
    do_usage(argv[0]);
    ~~~~~~~~        ^
1 warning generated.

The code that chooses between materialization of a non-correlated
IN subquery and its transformation into an EXISTS correlated
subquery assumes that the execution plan for the outer select
has been already built. However it was not always so if subqueries
occurred in the expressions used for ref access to tables of
the outer select. A call of the function create_ref_for_key() in
get_best_combination() could trigger a premature execution of
the above mentioned code when the execution plan structures for
the outer select were not fully built. This could cause a crash
of the server.

The fix postpones the calls of create_ref_for_key() until the
structures for the execution plan is fully built.

commit 1198267c331b045b9cad26be72b1a5b4f8930a79
Author: Thirunarayanan Balathandayuthapani <thirunarayanan.balathandayuth@oracle.com>
Date:   Fri Aug 26 11:00:44 2016 +0530

    Bug #20989615   INNODB AUTO_INCREMENT PRODUCES SAME VALUE TWICE

The code fix is already present.

commit 12343617922cfd9c48ee84ad6ecf53068d822010
Author: Thirunarayanan Balathandayuthapani <thirunarayanan.balathandayuth@oracle.com>
Date:   Fri Jul 15 14:39:37 2016 +0530

    Bug #23475211   COMBINING ALTER OPERATIONS TRIGGERS TABLE REBUILD

The code fix is already present.

The implementation of the walk method for the class Item_in_subselect
was missing. As a result the method never traversed the left operand
of any IN subquery predicate.

Item_exists_subselect::exists2in_processor() that performs the
Exist-To-In transformation calls the walk method to collect info
on outer references. As the walk method did not traverse the
left operands of the IN subqueries the outer references there
were not taken into account and some subqueries that were actually
correlated were marked as uncorrelated. It could lead to an
attempt of the materialization of such a subquery.

Also added a cleanup for some test cases merged from 5.5.

after building with system

On 64-bit Windows, sizeof(ulint)!=sizeof(ulong).

This is a reduced version of an originally much larger patch.
We will keep the definition of the ulint, lint data types unchanged,
and we will not be replacing fprintf() calls with ib_logf().

On Windows, use the standard format strings instead of nonstandard
extensions.

This patch fixes some errors in format strings.
Most notably, an IMPORT TABLESPACE error message in InnoDB was
displaying the number of columns instead of the mismatching flags.

of course, this combination can never succeed,
we must fail to connect here.

MDEV-12230 include/my_sys.h:600:43: error: unknown type name ‘PSI_file_key’" when -DWITHOUT_SERVER=1

cherry-pick 2c2bd8c1 (MDEV-12261 build failure without P_S) from 10.0

it could be
* O_SEARCH on Illumos
* O_EXEC on FreeBSD
* O_PATH on Linux
ugh

way-too-smart compilers don't like the "confusing indentation"

Allow 64-bit atomic operations on 32-bit systems,
only relying on HAVE_ATOMIC_BUILTINS_64, disregarding
the width of the register file.

Define UNIV_WORD_SIZE correctly on all systems, including Windows.
In MariaDB 10.0 and 10.1, it was incorrectly defined as 4 on
64-bit Windows.

Define HAVE_ATOMIC_BUILTINS_64 on Windows
(64-bit atomics are available on both 32-bit and 64-bit Windows
platforms; the operations were unnecessarily disabled even on
64-bit Windows).

MONITOR_OS_PENDING_READS, MONITOR_OS_PENDING_WRITES: Enable by default.

os_file_n_pending_preads, os_file_n_pending_pwrites,
os_n_pending_reads, os_n_pending_writes: Remove.
Use the monitor counters instead.

os_file_count_mutex: Remove. On a system that does not support
64-bit atomics, monitor_mutex will be used instead.

The motivation for this is that Perl is moving towards not having
current directory ./ in @INC by default. This is causing
mysql-test-run.pl to fail in latest Debian Unstable:

  https://lists.debian.org/debian-devel-announce/2016/08/msg00013.html

However, we have `use "lib"`, there is no need for current directory
in @INC, except for a gross hack. In mtr_cases.pm, there is a
`require "mtr_misc.pl"`, which hides mtr_misc.pl away in mtr_cases
namespace. And things only work because mysql-test-run.pl loads it
with a different name, `require "lib/mtr_misc.pl"`! (Perl will
`require` only once for each unique filename).

Fix this by only using `require` in main program, and referencing
functions with :: scope from other namespaces. For multi-use in
different namespaces, proper `use` modules should be used.
Signed-off-by: Kristian Nielsen <knielsen@knielsen-hq.org>