When analyzing the possible index use cases the server was re-using an internal structure.
This is wrong, as this internal structure gets updated during the analysis.
Fixed by making a copy of the internal structure for every place it needs to be used.
Also stopped the generation of empty SEL_TREE structures that unnecessary 
complicate the analysis.

mysql-test/r/index_merge.result:
  Bug#37943: test case
mysql-test/t/index_merge.test:
  Bug#37943: test case
sql/opt_range.cc:
  Bug#37943: 
   - Make copy constructors for SEL_TREE and sub-structures and use them when OR-ing trees.
   - don't generate empty SEL_TREEs. Return NULL instead.

Re-enabling failing test case because server logs were lost in pushbuild, so we need to run it again.


mysql-test/suite/rpl/t/disabled.def:
  Re-enabling failing test case because server logs were lost in pushbuild, so we need to run it again.

This patch contains fixes for two problems:

1. As originally reported, the server crashed on Mac OS X when trying to access
   an EXAMPLE table after the EXAMPLE plugin was installed.

   It turned out that the dynamically loaded EXAMPLE plugin called the
   function hash_earch() from a Mac OS X system library, instead of
   hash_earch() from MySQL's mysys library. Makefile.am in storage/example
   does not include libmysys. So the Mac OS X linker arranged the hash_search()
   function to be linked to the system library when the shared object is
   loaded.

   One possible solution would be to include libmysys into the linkage of
   dynamic plugins. But then we must have a libmysys.so, which must be
   used by the server too. This could have a minimal performance impact,
   but foremost the change seems to bee too risky at the current state of
   MySQL 5.1.

   The selected solution is to rename MySQL's hash_search() to my_hash_search()
   like it has been done before with hash_insert() and hash_reset().

   Since this is the third time, we need to rename a hash_*() function,
   I did renamed all hash_*() functions to my_hash_*().

   To avoid changing a zillion calls to these functions, and announcing
   this to hundreds of developers, I added defines that map the old names
   to the new names.

   This change is in hash.h and hash.c.

2. The other problem was improper implementation of the handlerton-to-plugin
   mapping. We use a fixed-size array to hold a plugin reference for each
   handlerton. On every install of a handler plugin, we allocated a new slot
   of the array. On uninstall we did not free it. After some uninstall/install
   cycles the array overflowed. We did not check for overflow.

   One fix is to check for overflow to stop the crashes.

   Another fix is to free the array slot at uninstall and search for a free slot
   at plugin install.

   This change is in handler.cc.



include/hash.h:
  Bug#37958 - test main.plugin crash on Mac OS X when selecting from EXAMPLE engine.
  Renamed hash_*() functions to my_hash_*().
  Added defines that map old names to new names.
mysys/hash.c:
  Bug#37958 - test main.plugin crash on Mac OS X when selecting from EXAMPLE engine.
  Renamed hash_*() functions to my_hash_*().
sql/handler.cc:
  Bug#37958 - test main.plugin crash on Mac OS X when selecting from EXAMPLE engine.
  Protect against a failing ha_initialize_handlerton() in ha_finalize_handlerton().
  Free hton2plugin slot on uninstall of a handler plugin.
  Reuse freed slost of the hton2plugin array.
  Protect against array overrun.

Repush of change to fix tests on Pushbuild.

Link with mtmalloc on Solaris as it is done in our release builds.
Replace deprecated flag with the newer option as already done in
other scripts.

BUILD/compile-solaris-amd64-forte:
  Link to mtmalloc and replace deprecated flag.
BUILD/compile-solaris-amd64-forte-debug:
  Replace deprecated flag.
BUILD/compile-solaris-sparc:
  Link to mtmalloc.
BUILD/compile-solaris-sparc-forte:
  Link to mtmalloc

Post-merge bug fix: lock_type is a enumeration type and not a bit mask.

sql/sql_cache.cc:
  Check for lock type explicitly. Also err on the safe side and
  invalidate the query cache for any write lock.

Server created "arc" directories inside database directories and
maintained there useless copies of .frm files.

Creation and renaming procedures of those copies as well as
creation of "arc" directories has been discontinued.
Removal procedure has been kept untouched to be able to
cleanup existent database directories by the DROP DATABASE
query. Also view renaming procedure has been updated to remove
these directories.


sql/parse_file.cc:
  Fixed bug #17823: 'arc' directories inside database directories.
  View/table creation and renaming procedures maintained
  backup copies of .frm files. Those copies are unused yet,
  so this feature was incomplete and unnecessary.
  
  1. Unwanted code has been hidden by FRM_ARCHIVE ifdefs
  (the FRM_ARCHIVE macro is not defined).
  
  2. Renaming procedure has been modified to remove obsolete
  "arc" directories.
sql/parse_file.h:
  Fixed bug #17823: 'arc' directories inside database directories.
  The "thd" parameter has been added to the rename_in_schema_file()
  function.
sql/sql_db.cc:
  Fixed bug #17823: 'arc' directories inside database directories.
  Scope of the mysql_rm_arc_files() function has been changed to
  global for use from the parse_file.cc file.
sql/sql_view.cc:
  Fixed bug #17823: 'arc' directories inside database directories.
  Added the "thd" argument to rename_in_schema_file() calls.

     JOIN for the subselect wasn't cleaned if we came upon an error
     during sub_select() execution. That leads to the assertion failure
     in close_thread_tables()

     part of the 6.0 code backported

per-file comments:
  mysql-test/r/sp-error.result
Bug#37949 Crash if argument to SP is a subquery that returns more than one row 
    test result

  mysql-test/t/sp-error.test
Bug#37949 Crash if argument to SP is a subquery that returns more than one row 
    test case

  sql/sp_head.cc
Bug#37949 Crash if argument to SP is a subquery that returns more than one row 
    lex->unit.cleanup() call added if not substatement

The problem is that when statement-based replication was enabled,
statements such as INSERT INTO .. SELECT FROM .. and CREATE TABLE
.. SELECT FROM need to grab a read lock on the source table that
does not permit concurrent inserts, which would in turn be denied
if the source table is a log table because log tables can't be
locked exclusively.

The solution is to not take such a lock when the source table is
a log table as it is unsafe to replicate log tables under statement
based replication. Furthermore, the read lock that does not permits
concurrent inserts is now only taken if statement-based replication
is enabled and if the source table is not a log table.

include/thr_lock.h:
  Introduce yet another lock type that my get upgraded depending
  on the binary log format. This is not a optimal solution but
  can be easily improved later.
mysql-test/r/log_tables.result:
  Add test case result for Bug#34306
mysql-test/suite/binlog/r/binlog_stm_row.result:
  Add test case result for Bug#34306
mysql-test/suite/binlog/t/binlog_stm_row.test:
  Add test case for Bug#34306
mysql-test/t/log_tables.test:
  Add test case for Bug#34306
sql/lock.cc:
  Assert that TL_READ_DEFAULT is not a real lock type.
sql/mysql_priv.h:
  Export new function.
sql/mysqld.cc:
  Remove using_update_log.
sql/sql_base.cc:
  Introduce function that returns the appropriate read lock type
  depending on how the statement is going to be replicated. It will
  only take a TL_READ_NO_INSERT log if the binary is enabled and the
  binary log format is statement-based and the table is not a log table.
sql/sql_parse.cc:
  Remove using_update_log.
sql/sql_update.cc:
  Use new function to choose read lock type.
sql/sql_yacc.yy:
  The lock type is now decided at open_tables time. This old behavior was
  actually misleading as the binary log format can be dynamically switched
  and this would not change for statements that have already been parsed
  when the binary log format is changed (ie: prepared statements).

      
In order to improve the performance when replicating to partitioned
myisam tables with row-based format, the number of rows of current 
rows log event is estimated and used to setup storage engine for bulk
inserts.

Bug#38311 - Fix of some cruft from remove_files in ndb_autodiscover.test, clean up of distinct.test,
and replacing error numbers with error names.

Trimmed some error-prone and variable portions of the test and added 'flush status' to ensure deterministic test

mysql-test/lib/mtr_cases.pl:
  forward port the algorithm to check if a binlog format is supported
mysql-test/mysql-test-run.pl:
  Don't use dynamic setting of binlog format - does not work

            
A stored procedure involving substrings could crash the server on certain
platforms because of invalid memory reads.
          
During storing the new blob-field value, the cached value's address range
overlapped that of the new field value. This caused problems when the 
cached value storage was reallocated to provide access for a new 
characater set representation. The patch checks the address ranges, and if
they overlap, the new field value is copied to a new storage before it is
converted to the new character set.


mysql-test/r/sp.result:
  Added result set
mysql-test/t/sp.test:
  Added test case
sql/field.cc:
  The source and destination address ranges of a character conversion must not overlap or the 'from' address will be invalidated as the temporary value-
  object is re-allocated to fit the new character set.
sql/field.h:
  Added comments