The problem reported is a compile bug,
reported by the development GCC team with GCC 4.2.

The original issue can no longer be reproduced in MySQL 5.1,
since the configure script no longer define HAVE_ATOMIC_ADD,
which caused the Linux atomic functions to be used (and cause a problem
with an invalid cast).

This patch implements some code cleanup for 5.1 only, which was identified
during the investigation of this issue.

With this patch, statistics maintained in THD::status_var are by definition
owned by the running thread, and do not need to be protected against race
conditions. These statistics are maintained by the status_var_* helpers,
which do not require any lock.

into  mockturtle.local:/home/dlenev/src/mysql-5.1-alter

and invalidation in the most general case (non-temporary table and
not simple RENAME or ENABLE/DISABLE KEYS or partitioning command).

See comment for sql/sql_table.cc for more information.

These changes are prerequisite for 5.1 version of fix for bug #23667
"CREATE TABLE LIKE is not isolated from alteration by other connections"

into  adventure.(none):/home/thek/Development/cpp/mysql-5.1-runtime

- Adding variable m_cached_result_type to keep the variable type consistent
  during the execution of a statement.
- Before each result set is returned to the client the description of each
  column is sent as meta data.
  Previously the result type for a column could change if the hash variable
  entry changed between statements. This caused the result set of the query
  to alternate column types in certain cases which is not supported by MySQL
  client-server protocol. Example:
  Previously this sequence:
    SET @A:=1;
    SELECT @A:="text", @A;
  would return "text", "text";
 
  After the change the SELECT returns "text", 0
  The reson for this is that previously the result set from 'SELECT @A;'
  would always be of the type STRING, whereas now the type of the variable
  is taken from the last SET statement. However, 'SELECT @A:="text"' will
  return type of STRING since the right side of the assignment is used.

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Adjust the check that defines the error message to be returned.

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into  adventure.(none):/home/thek/Development/cpp/bug27415/my51-bug27415

 - Problem was reported as a SP variable using itself as 
   right value inside SUBSTR caused corruption of data. 
 - This bug could not be verified in either 5.0bk or 5.1bk
 - Added test case to prevent future regressions.

(Bug#26338 "events_bugs.test fail on Debian")

open bug report, reproduced in the runtime team tree).

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into  vajra.(none):/opt/local/work/mysql-5.0-21483

Bug#21483 "Server abort or deadlock on INSERT DELAYED with another
implicit insert"
Also fixes and adds test cases for bugs:
20497 "Trigger with INSERT DELAYED causes Error 1165"
21714 "Wrong NEW.value and server abort on INSERT DELAYED to a
table with a trigger".
Post-review fixes.

Problem:
In MySQL INSERT DELAYED is a way to pipe all inserts into a
given table through a dedicated thread. This is necessary for
simplistic storage engines like MyISAM, which do not have internal
concurrency control or threading and thus can not
achieve efficient INSERT throughput without support from SQL layer.
DELAYED INSERT works as follows:
For every distinct table, which can accept DELAYED inserts and has
pending data to insert, a dedicated thread is created to write data
to disk. All user connection threads that attempt to
delayed-insert into this table interact with the dedicated thread in
producer/consumer fashion: all records to-be inserted are pushed
into a queue of the dedicated thread, which fetches the records and 
writes them.
In this design, client connection threads never open or lock
the delayed insert table.
This functionality was introduced in version 3.23 and does not take 
into account existence of triggers, views, or pre-locking.
E.g. if INSERT DELAYED is called from a stored function, which,
in turn, is called from another stored function that uses the delayed
table, a deadlock can occur, because delayed locking by-passes
pre-locking. Besides:
 * the delayed thread works directly with the subject table through
   the storage engine API and does not invoke triggers
 * even if it was patched to invoke triggers, if triggers,
   in turn, used other tables, the delayed thread would
   have to open and lock involved tables (use pre-locking).
 * even if it was patched to use pre-locking, without deadlock
   detection the delayed thread could easily lock out user 
   connection threads in case when the same table is used both
   in a trigger and on the right side of the insert query: 
   the delayed thread would not release locks until all inserts 
   are complete, and user connection can not complete inserts 
   without having locks on the tables used on the right side of the
   query.

Solution:

These considerations suggest two general alternatives for the
future of INSERT DELAYED:
 * it is considered a full-fledged alternative to normal INSERT
 * it is regarded as an optimisation that is only relevant 
   for simplistic engines.
Since we missed our chance to provide complete support of new
features when 5.0 was in development, the first alternative
currently renders infeasible.
However, even the second alternative, which is to detect
new features and convert DELAYED insert into a normal insert, 
is not easy to implement.
The catch-22 is that we don't know if the subject table has triggers
or is a view before we open it, and we only open it in the
delayed thread. We don't know if the query involves pre-locking
until we have opened all tables, and we always first create
the delayed thread, and only then open the remaining tables.
This patch detects the problematic scenarios and converts
DELAYED INSERT to a normal INSERT using the following approach:
 * if the statement is executed under pre-locking (e.g. from
   within a stored function or trigger) or the right
   side may require pre-locking, we detect the situation
   before creating a delayed insert thread and convert the statement
   to a conventional INSERT.
  * if the subject table is a view or has triggers, we shutdown
   the delayed thread and convert the statement to a conventional
   INSERT.

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into  vajra.(none):/opt/local/work/mysql-4.1-runtime

into  mockturtle.local:/home/dlenev/src/mysql-5.1-cts-3

TABLES" and failures of alter_table.test on Windows which occured after
pushing fix for bugs #20662, #20903, #24508, #24738 (various problems
with CREATE TABLE SELECT).

ALTER TABLE statements which were handled using "fast" alter table
optimization were not properly working under LOCK TABLES if table
was transactional (for all table types under Windows).

Code implementing "fast" version of ALTER TABLE tried to open and
lock table using open_ltable() after renaming .FRM files (which
corresponds to renaming tables in normal case) in some cases
(for transactional tables or on Windows). This caused problems
under LOCK TABLES and conflicted with name-lock taken by 
ALTER TABLE RENAME on target tables.

This patch solves this issue by using reopen_name_locked_table()
instead of open_ltable().

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into  bk-internal.mysql.com:/data0/bk/mysql-5.1-opt

into  bk-internal.mysql.com:/data0/bk/mysql-5.0-opt

into  olga.mysql.com:/home/igor/mysql-5.1-opt