Partitions can have different ref_length (position data length).
Removed DBUG_ASSERT which crashed debug builds when using
MAX_ROWS on some partitions.

               FAILS WITH LIBEDIT

Fixed by checking the return value of the write()
function calls and handling the open files and fd
appropriately.

calc_daynr() function returns negative result
if malformed date with zero year and month is used.
Attempt to calculate week day on negative value
leads to crash. The fix is return NULL for
'W', 'a', 'w' specifiers if zero year and month is used.
Additional fix for calc_daynr():
--added assertion that result can not be negative
--return 0 if zero year and month is used

Before sorting HAVING condition is split into two parts,
first part is a table related condition and the rest of is
HAVING part. Extraction of HAVING part does not take into account
the fact that some of conditions might be non-const but
have 'used_tables' == 0 (independent subqueries)
and because of that these conditions are cut off by
make_cond_for_table() function.
The fix is to use (table_map) 0 instead of used_tables in
third argument for make_cond_for_table() function.
It allows to extract elements which belong to sorted
table and in addition elements which are independend
subqueries.

Update for previous patch according to reviewers comments.

Updated the constructors for ha_partitions to use the common
init_handler_variables functions

Added use of defines for size and offset to get better readability for the code that reads
and writes the .par file. Also refactored the get_from_handler_file function.

             FAILS ON SOLARIS

This assertion was triggered if gethostbyaddr_r cannot do a
reverse lookup on an ip address. The reason was a missing
DBUG_RETURN macro. The problem affected only debug versions of
the server.

This patch fixes the problem by replacing return with DBUG_RETURN.
No test case added.

Bug#11764671  57533: UNINITIALISED VALUES IN COPY_AND_CONVERT (SQL_STRING.CC) WITH CERTAIN CHA
When ROUND evaluates decimal result it uses Item::decimal
value as fraction value for the result. In some cases
Item::decimal is greater than real result fraction value
and uninitialised memory of result(decimal) buffer can be
used in further calculations. Issue is introduced by
Bug33143 fix. The fix is to remove erroneous assignment.

Update test case

.0

The bug was fixed by the patch for bug number BUG 11763109 - 55779: SELECT
DOES NOT WORK PROPERLY IN MYSQL SERVER VERSION "5.1.42 SUSE MYSQL (Exact same
fix as was proposed for this bug.) Since the motivation for the two bug
reports was completely different, however, it still makes sense to push the
test case.

This patch contains only the test case.

Some multibyte sequences could be considered by my_mbcharlen() functions
as multibyte character but more exact my_ismbchar() does not think so.
In such a case this multibyte sequences is pushed into 'stack' buffer which
is too small to accommodate the sequence.
The fix is to allocate stack buffer in
compliance with max character length.

Instead of just filtering space, filter white space (\s)
I left the default.experimental file as is, with tabs.

Valgrind warnings were caused by comparing index values to an un-initialized field.

Fix for --vs-config applied
Find.pm incorrectly tested an unitialized local variable instead
  of the global, corrected.
Find.pm is also wrong in 5.5: uses a non-existent global variable. Fix when
  merging up.

There are two problems with ANALYSE():

1. Memory leak 
   it happens because do_select() can overwrite
   JOIN::procedure field(with zero value in our case) and
   JOIN destructor don't free the memory allocated for
   JOIN::procedure. The fix is to save original JOIN::procedure
   before do_select() call and restore it after do_select
   execution.

2. Wrong result
   If ANALYSE() procedure is used for the statement with LIMIT clause
   it could retrun empty result set. It happens because of missing 
   analyse::end_of_records() call. First end_send() function call
   returns NESTED_LOOP_QUERY_LIMIT and second call of end_send() with
   end_of_records flag enabled does not happen. The fix is to return
   NESTED_LOOP_OK from end_send() if procedure is active.

When we create temporary result table for UNION
incorrect max_length for YEAR field is used and
it leads to incorrect field value and incorrect
result string length as YEAR field value calculation
depends on field length.
The fix is to use underlying item max_length for
Item_sum_hybrid::max_length intialization.

Valgrind warning happens due to early null values check
in Item_func_in::fix_length_and_dec(before item evaluation).
As result null value items with uninitialized values are
placed into array and it leads to valgrind warnings during
value array sorting.
The fix is to check null value after item evaluation, item
is evaluated in in_array::set() method.

Select from a view with the underlying HAVING clause failed with a
message: "1356: View '...' references invalid table(s) or column(s)
or function(s) or definer/invoker of view lack rights to use them"

The bug is a regression of the fix for bug 11750328 - 40825 (similar
case, but the HAVING cause references an aliased field).
In the old fix for bug 40825 the Item_field::name_length value has
been used in place of the real length of Item_field::name. However,
in some cases Item_field::name_length is not in sync with the
actual name length (TODO: combine name and name_length into a
solid String field).

The Item_ref::print() method has been modified to calculate actual
name length every time.

               create_schema if auto-generate-sql also set.

mysqlslap uses a schema to run its tests on and later
drops it if auto-generate-sql is used. This can be a
problem, if the schema is an already existing one.

If create-schema is used with auto-generate-sql option,
mysqlslap while performing the cleanup, drops the specified
database.

Fixed by introducing an option --no-drop, which, if used,
will prevent the dropping of schema at the end of the test.