In particular:
Merged the patch for bug mdev-4418 from 5.3 into 5.5.
Fixed a bug in the patch that should be backported to 5.3.

After single row substitutions there might appear new equalities.
They should be properly propagated to all AND/OR levels the WHERE
condition. It's done now with an additional call of remove_eq_conds(). 

This patch almost totally revised the patch for bug mdev-4177.
The latter had too many defects. In particular, it did not
propagate multiple equalities formed when merging a degenerate
disjunct into underlying AND formula.

This a an old legacy performance bug.
When a very selective range scan existed for the second table in a join,
and, at the same time, there was another range condition depending on the
fields of the first table, the optimizer chose a plan with
'Range checked for each record'. This plan was extremely inefficient in
comparison with the regular selective range scan.
As a matter of fact the range scan chosen for each record was the same as
that selective range scan. 

Changed the test case for bug 24776 to preserve the old output for explain.
 

modified:
  mysql-test/r/dyncol.result
  mysql-test/r/type_time.result
  mysql-test/t/dyncol.test
  mysql-test/t/type_time.test
  mysys/ma_dyncol.c
  sql/item.cc
  sql/item_func.cc
pending merges:
  Alexander Barkov 2013-08-12 MDEV-4652 Wrong result for CONCAT(GREATEST(T...
    sanja@montyprogr... 2013-08-01 MDEV-4811 Assertion `offset < 0x1f' f...

set num_flag[] unconditionally, not under "if (column_names)"

http://ronaldbradford.com/blog/unexplained-trivial-mysql-behavior-2013-08-02/

pending merges:
  Alexander Barkov 2013-08-08 MDEV-4653 Wrong result for CONVERT_TZ(TIME('...

pending merges:
  Alexander Barkov 2013-08-08 MDEV-4512 Valgrind warnings in my_long10_to_...

Fixing a typo:  bit AND (&) was erroneously used instead of logical AND (&&) 

partitioning enhancement for Bug#14521864

engine

MDEV-4812 Valgrind warnings (Invalid write) in dynamic_column_update_many on COLUMN_ADD

Fixed problem of working on wrong data (do not allow offset to out of string length).

MDEV-4823: Server crashes in Item_func_not::fix_fields on creating a table with a virtual column using NOT

fix_field() call protocol was brocken (zero pointer passed as link to item which is possible only if you are sure that there can not be Items which transforms).

- Modify the way Item_cond::fix_fields() and Item_cond::eval_not_null_tables() 
  calculate bitmap for Item_cond_or::not_null_tables():
  if they see a "... OR inexpensive_const_false_item OR ..." then the item can
  be ignored.
- Updated test results. There can be more warnings produced since parts of WHERE 
  are evaluated more times.

MDEV-4815 - allow multiple  mysql_server_init() / mysql_server_end() in the same process, for embedded library.

- Reset  static variables that are used to signal "init done"  for DBUG, in dbug_end()
- Set string server variables to NULL after memory for the value is freed - avoids double free()
- fix DBUG_ASSERTs that happened during reinitialization.

- Let _ma_record_pos() set SEARCH_PART_KEY when doing a search on
  a prefix of a [unique] key.  Otherwise, _ma_search_pos() would 
  find the first key equal to search key, and assume it is also 
  the last one, which will make a wrong estimate of key's position.

  A wrong key position may cause min_pos > max_pos and records_in_range()
  will return 0, which will make the optimizer think it's an impossible 
  range while in fact it is not.

   not_enough_points() introduced to check if the spatial object is incorrect.

(fix of http://bugs.mysql.com/bug.php?id=69623)

  
In the case of loose scan used as input for order by, end_send()
didn't detect correctly that a loose scan was used, and didn't copy
the non-aggregated fields from the temp table used for ORDER BY.
  
The fix uses the fact that the quick select used for sorting is
attached to JOIN::pre_sort_join_tab instead of JOIN::join_tab.

MDEV-4782: Valgrind warnings (Conditional jump or move depends on uninitialised value) with InnoDB, semijoin
- in sub_select(): don't call table->file->position() when reading the first record
  produced an error.

Backport the fix olav.sandstaa@sun.com-20101102184747-qfuntqwj021imy9r:
"Fix for Bug#52660 Perf. regr. using ICP for MyISAM on range queries on an index containing TEXT" 
(together with further fixes in that code) into MyISAM and Aria.