- Make elimination check to be able detect cases like  t.primary_key_col1=othertbl.col AND t.primary_key_col2=func(t.primary_key_col1).
  These are needed to handle e.g. the case of func() being a correlated subquery that selects the latest value.
- If we've removed a condition with subquery predicate, EXPLAIN [EXTENDED] won't show the subquery anymore

sql/item.cc:
  MWL#17: Table elimination
  - Add tem_field::check_column_usage_processor(). it allows to check which key parts a condition depends on.
sql/item.h:
  MWL#17: Table elimination
  - Add tem_field::check_column_usage_processor(). it allows to check which key parts a condition depends on.
sql/item_subselect.cc:
  MWL#17: Table elimination
  - Item_subselect got 'eliminated' attribute. It is used only to determine if the subselect should be printed by EXPLAIN.
  - Item_subselect got List<Item> refers_to - a list of item in the current select that are referred to from within the subselect.
  - Added Item_*::check_column_usage_processor(). it allows to check which key parts a condition depends on.
  - Added a comment about possible problem in Item_subselect::walk
sql/item_subselect.h:
  MWL#17: Table elimination
  - Item_subselect got 'eliminated' attribute. It is used only to determine if the subselect should be printed by EXPLAIN.
  - Item_subselect got List<Item> refers_to - a list of item in the current select that are referred to from within the subselect.
  - Added Item_*::check_column_usage_processor(). it allows to check which key parts a condition depends on.
sql/item_sum.cc:
  MWL#17: Table elimination
sql/sql_lex.cc:
  MWL#17: Table elimination
sql/sql_lex.h:
  MWL#17: Table elimination
sql/sql_select.h:
  MWL#17: Table elimination

* Fix test results to account for changes in previous cset

* Change valgrind suppression to work on valgrind 3.3.0

- Move eliminate_tables() to before constant table detection. 
- First code for benchmark

sql-bench/test-table-elimination.sh:
  MWL#17: Table elimination
  - sql-bench "Benchmark", incomplete
sql/sql_select.cc:
  MWL#17: Table elimination
  - Move eliminate_tables() to before constant table detection, this will allow
    to spare const table reads (at a cost of not being able to take advantage of 
    tables that are constant because they have no records, but this case is of 
    lesser importance)

- Fix print_join() to work both for EXPLAIN EXTENDED (after table elimination) and for 
  CREATE VIEW (after join->prepare() but without any optimization).

mysql-test/r/union.result:
  MWL#17: Table elimination
  - Adjust test results

- Fix the previous cset: take into account that select_lex may be printed when 
 1. There is no select_lex->join at all (in that case, assume that no tables were eliminated)
 2. select_lex->join exists but there was no JOIN::optimize() call yet. handle this by initializing join->eliminated really early. 

- Do not show eliminated tables in the output of EXPLAIN EXTENDED

- Make elimination work with aggregate functions. The problem was that aggregate functions 
  reported all table bits in used_tables(), and that prevented table elimination. Fixed by 
  making aggregate functions return more correct value from used_tables(). 

mysql-test/r/ps_11bugs.result:
  MWL#17: Table elimination
  - Update test results. The difference is because of Item_ref change: outer references to constants
    are now recognized as constants, too.
mysql-test/r/subselect.result:
  - Update test results. The difference is because of Item_ref change: outer references to constants
    are now recognized as constants, too.
mysql-test/r/table_elim.result:
  MWL#17: Table elimination
  - Check that elimination works in presense of aggreagate functions
mysql-test/t/table_elim.test:
  MWL#17: Table elimination
  - Check that elimination works in presense of aggreagate functions
sql/item.h:
  MWL#17: Table elimination
  - Add Item_ref::const_item() which calls (*ref)->const_item(). Before this diff Item_ref used the 
    default implementation of const_item(){ return used_tables()==0; }. This is no longer true, as 
    COUNT(*) now has used_tables()==0 but const_item()==FALSE.
sql/item_sum.cc:
  MWL#17: Table elimination
  - Make Item_sum() and it descendants not to return all bits in used_tables(). This is needed 
    because otherwise table elimination can't work in presense of aggregate functions
  - COUNT(*) now has used_tables()==0 and const_item()==FALSE. Had to change 
    Item_ref::const_item() to account for this.
sql/item_sum.h:
  MWL#17: Table elimination
  - Add comments

  handle overlapping.

include/m_string.h:
  Fix valgrind failure: provide an implementation of strmov_overlapp() that really can handle overlapping.

- Fix trivial valgrind warning

- First code. Elimination works for simple cases, passes the testsuite.
- Known issues:
  = No elimination is done for aggregate functions.
  = EXPLAIN EXTENDED shows eliminated tables (I think it better not)
  = No benchmark yet
  = The code needs some polishing.

mysql-test/r/table_elim.result:
  MWL#17: Table elimination
  - Testcases
mysql-test/t/table_elim.test:
  MWL#17: Table elimination
  - Testcases
sql/sql_select.cc:
  MWL#17: Table elimination
sql/sql_select.h:
  MWL#17: Table elimination
  - Added JOIN_TAB::eliminated (is JOIN_TAB the best place to store this flag?)
sql/table.h:
  MWL#17: Table elimination
  - ADded NESTED_JOIN::n_tables. We need to have the number of real tables remaining in an outer join nest.

mysql-test/suite/maria/r/maria3.result:
  Merged fix from bug #39200.
mysql-test/suite/maria/t/maria3.test:
  Merged maria3.test
sql/sql_table.cc:
  Bug fix for 39200

 - Version number.
 - Valgrind false alarms in libz.
 - New variant of suppression for Valgrind warning in dlclose().
 - Fix double free() in plugin init error case.

configure.in:
  Fix version number. We should reset the maria variant back to `1' when the MySQL version
  number increases.
include/my_sys.h:
  Fix false alarms in Valgrind for zlib.
  
  Apply same fix as for archive storage handler also to the cases of compression in the
  client protocol, and to the compression SQL function.
mysql-test/valgrind.supp:
  A new variant of the dlclose() suppression is needed now.
mysys/my_compress.c:
  Fix false alarms in Valgrind for zlib.
  
  Apply same fix as for archive storage handler also to the cases of compression in the
  client protocol, and to the compression SQL function.
sql/handler.cc:
  Fix a double free() in error case for plugin initialisation.
sql/item_strfunc.cc:
  Fix false alarms in Valgrind for zlib.
  
  Apply same fix as for archive storage handler also to the cases of compression in the
  client protocol, and to the compression SQL function.

support-files/build-tags:
  Merge.

mysql-test/r/information_schema.result:
  Fixed a result file.
mysql-test/r/innodb-autoinc.result:
  Fixed a result file.
mysql-test/t/connect.test:
  Fixed a problem with merge, needed to close
  connections and use the default

mysql-test/mysql-test-run.pl:
  Fixed missed lines in merge.
storage/maria/plug.in:
  Fixed problem with configuration. This is now included
  top level.
storage/pbxt/plug.in:
  Fixed problem with configuration. This is
  included now in top level.

Portability changes for Solaris 10 (amd64). Re-hash BUILD/ scripts for Solaris to be more in line with generic scripts.

Consequently, rename HAVE_purify to HAVE_valgrind, and related changes.
Leave some comments about purify when not clear that they apply also to Valgrind.
Fix redundant IF_VALGRIND declaration.

Misc. small fixes:
 - Fixes for pool-of-threads patch.
 - Fixes for push of PBXT storage engine.
 - mysql-test-run.pl fix.
 - Fix build problem in compile-pentium64-max.


BUILD/SETUP.sh:
  Rename purify -> valgrind.
BUILD/build_mccge.sh:
  Rename purify -> valgrind.
BUILD/compile-dist:
  Fix that PBXT was missing in source tarball after `BUILD/compile-dist && make dist`
BUILD/compile-pentium64-max:
  Fix a build problem with BUILD/compile-pentium64-max on CentOS/Fedora Core 10 amd64.
        
  On these systems, there is libz.so but no libz.a. Finding libz.so, ./configure decides
  to use system zlib. But since BUILD/compile-pentium64-max builds a fully static binary
  with -all-static, the link of mysqld fails due to missing libz.a.
        
  Fix by using bundled zlib in the build script.
BUILD/compile-solaris-sparc-purify:
  Rename purify -> valgrind.
include/m_string.h:
  Rename purify -> valgrind.
include/my_global.h:
  Rename purify -> valgrind.
mysql-test/Makefile.am:
  Fix that PBXT test suite was missing from `make dist` source tarball.
mysql-test/lib/mtr_unique.pm:
  Better fix to avoid races when chmod'ing the semaphore file.
  (Though using chmod 666 shared files in /tmp/ is still not a very good solution).
mysql-test/t/pool_of_threads.cnf:
  Fix that test case pool_of_threads fails if run on mysqld with no --with-libevent support.
mysys/mf_qsort.c:
  Rename purify -> valgrind.
mysys/my_alloc.c:
  Rename purify -> valgrind.
mysys/my_init.c:
  Rename purify -> valgrind.
mysys/my_rnd.c:
  Rename purify -> valgrind.
mysys/safemalloc.c:
  Rename purify -> valgrind.
scripts/mysql_config.pl.in:
  Rename purify -> valgrind.
scripts/mysql_config.sh:
  Rename purify -> valgrind.
sql/field_conv.cc:
  Rename purify -> valgrind.
sql/filesort.cc:
  Rename purify -> valgrind.
sql/ha_partition.cc:
  Rename purify -> valgrind.
sql/hostname.cc:
  Rename purify -> valgrind.
sql/item_timefunc.cc:
  Rename purify -> valgrind.
sql/log_event.cc:
  Rename purify -> valgrind.
sql/log_event_old.cc:
  Rename purify -> valgrind.
sql/my_decimal.h:
  Rename purify -> valgrind.
sql/mysqld.cc:
  Rename purify -> valgrind.
  Fix redundant IF_VALGRIND declaration.
sql/opt_range.cc:
  Rename purify -> valgrind.
sql/opt_range.h:
  Rename purify -> valgrind.
sql/records.cc:
  Rename purify -> valgrind.
sql/rpl_rli.cc:
  Rename purify -> valgrind.
sql/rpl_rli.h:
  Rename purify -> valgrind.
sql/set_var.cc:
  Fix missing static declaration on pool_of_threads.
sql/slave.cc:
  Rename purify -> valgrind.
sql/sql_base.cc:
  Rename purify -> valgrind.
sql/sql_binlog.cc:
  Rename purify -> valgrind.
sql/sql_class.cc:
  Rename purify -> valgrind.
sql/sql_list.h:
  Rename purify -> valgrind.
sql/sql_load.cc:
  Rename purify -> valgrind.
sql/sql_select.cc:
  Rename purify -> valgrind.
sql/table.cc:
  Rename purify -> valgrind.
storage/archive/azio.c:
  Rename purify -> valgrind.
storage/innobase/buf/buf0buf.c:
  Rename purify -> valgrind.
storage/innobase/include/univ.i:
  Rename purify -> valgrind.
storage/innobase/srv/srv0start.c:
  Rename purify -> valgrind.
storage/maria/ha_maria.cc:
  Rename purify -> valgrind.
storage/maria/ma_blockrec.c:
  Rename purify -> valgrind.
storage/maria/ma_check.c:
  Rename purify -> valgrind.
storage/maria/ma_loghandler.c:
  Rename purify -> valgrind.
storage/maria/ma_packrec.c:
  Rename purify -> valgrind.
storage/maria/ma_page.c:
  Rename purify -> valgrind.
storage/maria/ma_pagecrc.c:
  Rename purify -> valgrind.
storage/maria/ma_search.c:
  Rename purify -> valgrind.
storage/myisam/mi_check.c:
  Rename purify -> valgrind.
storage/myisam/mi_page.c:
  Rename purify -> valgrind.
storage/myisam/mi_search.c:
  Rename purify -> valgrind.
storage/myisammrg/ha_myisammrg.cc:
  Rename purify -> valgrind.
strings/bcmp.c:
  Rename purify -> valgrind.
strings/decimal.c:
  Rename purify -> valgrind.
strings/strmake.c:
  Rename purify -> valgrind.

client/mysqltest.cc:
  Manually merged
configure.in:
  Manually merged
mysql-test/r/variables.result:
  Manually merged
mysql-test/t/variables.test:
  Manually merged
mysys/my_pread.c:
  Manually merged
mysys/my_read.c:
  Manually merged
sql/mysqld.cc:
  Manually merged
storage/csv/ha_tina.h:
  Manually merged
storage/myisam/ha_myisam.cc:
  Manually merged
storage/myisam/mi_check.c:
  Manually merged
storage/myisam/mi_search.c:
  Manually merged

configure.in:
  Manually merged
mysql-test/lib/My/ConfigFactory.pm:
  Manually merged
mysql-test/mysql-test-run.pl:
  Manually merged
mysql-test/t/information_schema.test:
  Manually merged
sql/handler.cc:
  Manually merged
support-files/mysql.spec.sh:
  Manually merged

sql/sql_string.cc:
  Optimized tests to do fewer reallocs
sql/strfunc.cc:
  Indentation fix

Fix mysql-test-run.pl to not terminate early when warnings in error logs are detected during
server shutdown. Instead, give a nice summary report at the end of the failures.

Fix code to make 100% sure no failures will go undetected.

Revert earlier wrong change.

Fix race with port allocation semaphore file permissions.

Adjust testsuite to copy with new PBXT engine now in the tree. The PBXT engine causes an
extra table to appear in the INFORMATION_SCHEMA. This causes different output for a few
test cases.

dbug/dbug.c:
  If DbugParse() is called multiple times, the stack->keywords for the
  top stack frame could be overwritten without being freed, causing a
  memory leak reported by Valgrind.
include/my_global.h:
  Add useful macro for different values when Valgrind (HAVE_purify) and not.
mysql-test/extra/rpl_tests/rpl_auto_increment.test:
  Omit pbxt variables from show variables output.
mysql-test/include/have_pbxt.inc:
  Add facility to disable test if PBXT engine is not available.
mysql-test/lib/mtr_report.pm:
  Give a nice summary report at the end of tests of any warnings seen in logs during
  server shutdowns.
mysql-test/lib/mtr_unique.pm:
  Move chmod 777 to greatly reduce the risk of leaving the port semaphore file unaccessible
  bu other users.
mysql-test/mysql-test-run.pl:
  Don't abort in case of warnings detected, instead give a nice summary report.
  
  Fix code to make 100% sure no failures will go undetected.
  
  Revert earlier wrong change when master disconnects early.
mysql-test/r/information_schema.result:
  Omit PBXT INFORMATION_SCHEMA table from output.
  Move part of test to information_schema_all_engines.
mysql-test/r/information_schema_all_engines.result:
  New file for information_schema tests that depend on which engines are available.
mysql-test/r/information_schema_db.result:
  Move part of test to information_schema_all_engines.
mysql-test/r/innodb-autoinc.result:
  Omit pbxt variables from show variables output.
mysql-test/r/mysqlshow.result:
  Move part of test to information_schema_all_engines.
mysql-test/suite/rpl/r/rpl_auto_increment.result:
  Omit pbxt variables from show variables output.
mysql-test/t/information_schema.test:
  Omit PBXT INFORMATION_SCHEMA table from output.
  Move part of test to information_schema_all_engines.
mysql-test/t/information_schema_all_engines.test:
  New file for information_schema tests that depend on which engines are available.
mysql-test/t/information_schema_db.test:
  Move part of test to information_schema_all_engines.
mysql-test/t/innodb-autoinc.test:
  Omit pbxt variables from show variables output.
mysql-test/t/mysqlshow.test:
  Move part of test to information_schema_all_engines.
mysql-test/valgrind.supp:
  Add variant suppression (different system library versions).
  Add suppression for problem with inet_ntoa().
sql/mysqld.cc:
  Fix missing DBUG_RETURN.
  Fix uninitialised thd->connect_utime, likely introduced by pool_of_threads.
sql/set_var.cc:
  Fix one-byte buffer overflow in several places.
  Fix unsafe use of String::c_ptr() of stack-allocated String buffer.
sql/sql_select.cc:
  Silence valgrind warning due to GCC bug.
sql/sql_string.h:
  Document potential problem with String::c_ptr() and String() constructor with caller-supplied buffer.
storage/archive/azio.c:
  Silence Valgrind false warning for libz.