Fixed the references to security_ctx->priv_user
to be real char * pointers instead of a C array name reference.
This is somehow important for some 3d party 
dtrace replacements

Backport from 5.5. OK from Anitha G. to push to 5.1.

Removed floor(float_col) tests, enabled floor(decimal_col) tests

--Bug#52157 various crashes and assertions with multi-table update, stored function
--Bug#54475 improper error handling causes cascading crashing failures in innodb/ndb
--Bug#57703 create view cause Assertion failed: 0, file .\item_subselect.cc, line 846
--Bug#57352 valgrind warnings when creating view
--Recently discovered problem when a nested materialized derived table is used
  before being populated and it leads to incorrect result

We have several modes when we should disable subquery evaluation.
The reasons for disabling are different. It could be
uselessness of the evaluation as in case of 'CREATE VIEW'
or 'PREPARE stmt', or we should disable subquery evaluation
if tables are not locked yet as it happens in bug#54475, or
too early evaluation of subqueries can lead to wrong result
as it happened in Bug#19077.
Main problem is that if subquery items are treated as const
they are evaluated in ::fix_fields(), ::fix_length_and_dec()
of the parental items as a lot of these methods have
Item::val_...() calls inside.
We have to make subqueries non-const to prevent unnecessary
subquery evaluation. At the moment we have different methods
for this. Here is a list of these modes:

1. PREPARE stmt;
We use UNCACHEABLE_PREPARE flag.
It is set during parsing in sql_parse.cc, mysql_new_select() for
each SELECT_LEX object and cleared at the end of PREPARE in
sql_prepare.cc, init_stmt_after_parse(). If this flag is set
subquery becomes non-const and evaluation does not happen.

2. CREATE|ALTER VIEW, SHOW CREATE VIEW, I_S tables which
   process FRM files
We use LEX::view_prepare_mode field. We set it before
view preparation and check this flag in
::fix_fields(), ::fix_length_and_dec().
Some bugs are fixed using this approach,
some are not(Bug#57352, Bug#57703). The problem here is
that we have a lot of ::fix_fields(), ::fix_length_and_dec()
where we use Item::val_...() calls for const items.

3. Derived tables with subquery = wrong result(Bug19077)
The reason of this bug is too early subquery evaluation.
It was fixed by adding Item::with_subselect field
The check of this field in appropriate places prevents
const item evaluation if the item have subquery.
The fix for Bug19077 fixes only the problem with
convert_constant_item() function and does not cover
other places(::fix_fields(), ::fix_length_and_dec() again)
where subqueries could be evaluated.

Example:
CREATE TABLE t1 (i INT, j BIGINT);
INSERT INTO t1 VALUES (1, 2), (2, 2), (3, 2);
SELECT * FROM (SELECT MIN(i) FROM t1
WHERE j = SUBSTRING('12', (SELECT * FROM (SELECT MIN(j) FROM t1) t2))) t3;
DROP TABLE t1;

4. Derived tables with subquery where subquery
   is evaluated before table locking(Bug#54475, Bug#52157)

Suggested solution is following:

-Introduce new field LEX::context_analysis_only with the following
 possible flags:
 #define CONTEXT_ANALYSIS_ONLY_PREPARE 1
 #define CONTEXT_ANALYSIS_ONLY_VIEW    2
 #define CONTEXT_ANALYSIS_ONLY_DERIVED 4
-Set/clean these flags when we perform
 context analysis operation
-Item_subselect::const_item() returns
 result depending on LEX::context_analysis_only.
 If context_analysis_only is set then we return
 FALSE that means that subquery is non-const.
 As all subquery types are wrapped by Item_subselect
 it allow as to make subquery non-const when
 it's necessary.

  
On this platform we seem to get lots of other signals
while waiting for SIGKILL to be delivered.

Solution: use sigsuspend(<all signals blocked>)

Auto increment value wraps when performing a bulk insert with
auto_increment_increment and auto_increment_offset greater than
one.
The fix:
If overflow happened then return MAX_ULONGLONG value as an
indication of overflow and check this before storing the
value into the field in update_auto_increment().

  
On this platform we seem to get lots of other signals
while waiting for SIGKILL to be delivered.

Solution: use sigsuspend(<all signals blocked>)

Explain fails at fix_fields stage and some items are left unfixed,
particulary Item_group_concat. Item_group_concat::orig_args field
is uninitialized in this case and Item_group_concat::print call 
leads to crash.
The fix:
move the initialization of Item_group_concat::orig_args
into constructor.

DROP/CREATE SCHEMA, CREATE TABLE, REPAIR.

The cause of assert was concurrent execution of
DROP DATABASE and REPAIR TABLE where first statement
deleted table's file .TMD at the same time as
REPAIR TABLE tried to read file details from the old file
that was just removed.

Additionally was fixed trouble when DROP TABLE try delete
all files belong to table being dropped at the same time
when REPAIR TABLE statement has just deleted .TMD file.

No regression test added because this would require adding a
sync point to mysys/my_redel.c. Since this bug is not present in
5.5+, adding test coverage was considered unnecessary.
The patch has been verified using RQG testing.

The tests generates 4 Billion rows which timeouts.

Removed the test from the default weekly run.

mysqltest checks if the stmt is one that should be run in ps mode,
  but regexp doesn't match if preceeded by /* */ comment.
Fix: match function will jump over /*..*/ if found at start

Backported use of setenv() from 5.5
This will remove the leak on systems that have setenv()
I have not fixed the string.c leak, it's a local variable
   that the cleanup function cannot access.

Fixed some errors
Added note about 'no' prefix to options
See also follow-up comment to bug report

Workaround: add --loose-skip-innodb-use-native-aio
Only on linux if explicitly using --mem or setting $OPT_MEM

Add check that there is a RHS of the expression
Added to mysqltest.test

Var's string value was not 0-terminated if intially null.
While at it, also removed some reported memory leaks
Added sanity check, setting val_len=0 if val==0

Added option --debug-common which sets 'd' debug flags to the suggested list

 my_seek() and my_tell() functions now honour MY_WME flag.

 when semijoin=on

When setting the aggregate function as having no rows to report
the function no_rows_in_result() was calling Item_sum::reset().
However this function in addition to cleaning up the aggregate 
value by calling aggregator_clear() was also adding the current
value to the aggregate value by calling aggregator_add().
Fixed by making no_rows_in_result() to call aggregator_clear()
directly.
Renamed Item_sum::reset to Item_sum::reset_and_add() to
and added a comment to avoid misinterpretation of what the
function does.

Before this fix, the output of SHOW ENGINE PERFORMANCE_SCHEMA STATUS
used uppercase to name performance schema tables.

This is inconsistent since performance schema tables have been renamed to lowercase.

Also, an old table 'PROCESSLIST' was still visible, 
even after this table got renamed to 'threads'.

This fix:
- correctly uses lowercases in the output, to match the current naming.
- replaced 'PROCESSLIST' with 'threads'.

Tested the output of SHOW ENGINE PERFORMANCE_SCHEMA STATUS manually.
No automated test cases can be written for this, 
since the output is too platform dependent (sizes).

merged from mysql-5.5.8-release tree,
revision: ramil@mysql.com-20101203174908-217tdkn150vieha9

when there was one NULL value, AVG(DISTINCT) could forget about other values.
See commit comment of item_sum.cc.

Do not use the same maintainer mode flags for both GCC and ICC.
The -Wall option for ICC enables more warnings than its GCC
counterpart.