The crash happens because of incorrect max_length calculation
in QUOTE function(due to overflow). max_length is set
to 0 and it leads to assert failure.
The fix is to cast expression result to
ulonglong variable and adjust it if the
result exceeds MAX_BLOB_WIDTH.

There was no way to repair corrupt ARCHIVE data file,
when unrecoverable data loss is inevitable.

With this fix REPAIR ... EXTENDED attempts to restore
as much rows as possible, ignoring unrecoverable data.

Normal REPAIR is still able to repair meta-data file
only.

by sort and fulltext keys.

Min value for myisam_sort_buffer_size is 4096.

Repairing MyISAM table with fulltext indexes and low
myisam_sort_buffer_size may crash the server.

Estimation of number of index entries was done incorrectly,
causing further assertion failure or server crash.

Docs note: min value for myisam_sort_buffer_size has been
changed from 4 to 4096.

Invalid memory read if HANDLER ... READ NEXT is executed
after failed (e.g. empty table) HANDLER ... READ FIRST.

The problem was that we attempted to perform READ NEXT,
whereas there is no pivot available from failed READ FIRST.

With this fix READ NEXT after failed READ FIRST equals
to READ FIRST.

This bug affects MyISAM tables only.

When MyISAM writes newly created index page it may be
initialized partially. In other words some bytes of
sensible data and uninitialized tail of the page may
go into index file.

Under certain rare circumstances these hunks of memory
may contain data that would be otherwise inaccessible
to user, like passwords or data from other tables.

Fixed by initializing memory for temporary MyISAM key
buffer to '\0'.

No test case for this fix as it is heavily covered by
existing tests.

Detailed revision comments:

r6822 | vasil | 2010-03-15 10:17:31 +0200 (Mon, 15 Mar 2010) | 12 lines
branches/5.1:

Typecast to silence a compiler warning:

row/row0sel.c: 4548
        C4244: '=' : conversion from 'float' to 'ib_ulonglong', possible loss of data
row/row0sel.c: 4553
        C4244: '=' : conversion from 'double' to 'ib_ulonglong', possible loss of data

Reported by:	Jonas Oreland <Jonas.Oreland@Sun.COM>
Discussed with:	Sunny Bains <sunny.bains@oracle.com>

Detailed revision comments:

r6785 | vasil | 2010-03-10 09:04:38 +0200 (Wed, 10 Mar 2010) | 11 lines
branches/5.1:

Add the missing --reap statements in innodb_bug38231.test. Probably MySQL
enforced the presence of those recently and the test started failing like:

  main.innodb_bug38231                     [ fail ]
          Test ended at 2010-03-10 08:48:32
  
  CURRENT_TEST: main.innodb_bug38231
  mysqltest: At line 49: Cannot run query on connection between send and reap

r6788 | vasil | 2010-03-10 10:53:21 +0200 (Wed, 10 Mar 2010) | 8 lines
branches/5.1:

In innodb_bug38231.test: replace the fragile sleep 0.2 that depends on timing
with a more robust condition which waits for the TRUNCATE and LOCK commands
to appear in information_schema.processlist. This could also break if there
are other sessions executing the same SQL commands, but there are none during
the execution of the mysql test.

Detailed revision comments:

r6783 | jyang | 2010-03-09 17:54:14 +0200 (Tue, 09 Mar 2010) | 9 lines
branches/5.1: Fix bug #47621 "MySQL and InnoDB data dictionaries
will become out of sync when renaming columns". MySQL does not
provide new column name information to storage engine to
update the system table. To avoid column name mismatch, we shall
just request a table copy for now.

rb://246 approved by Marko.

Detailed revision comments:

r6780 | vasil | 2010-03-08 19:13:20 +0200 (Mon, 08 Mar 2010) | 4 lines
branches/5.1:

Whitespace fixup.

Detailed revision comments:

r6774 | calvin | 2010-03-03 23:56:10 +0200 (Wed, 03 Mar 2010) | 2 lines
branches/5.1: fix bug#51653: outdated reference to set-variable
Non functional change.

If the listed columns in the view definition of 
the table used in a 'INSERT .. SELECT ..'
statement mismatched, a debug assertion would
trigger in the cache invalidation code
following the failing statement.

Although the find_field_in_view() function
correctly generated ER_BAD_FIELD_ERROR during
setup_fields(), the error failed to propagate
further than handle_select(). This patch fixes
the issue by adding a check for the return
value.

The crash happens because greedy_serach
can not determine best plan due to
wrong inner table dependences. These
dependences affects join table sorting
which performs before greedy_search starting.
In our case table which has real 'no dependences'
should be put on top of the list but it does not
happen as inner tables have no dependences as well.
The fix is to exclude RAND_TABLE_BIT mask from
condition which checks if table dependences
should be updated.

  col equal to itself!

There's no need to copy the value of a field into itself.
While generally harmless (except for some performance penalties)
it may be dangerous when the copy code doesn't expect this.
Fixed by checking if the source field is the same as the destination
field before copying the data.
Note that we must preserve the order of assignment of the null 
flags (hence the null_value assignment addition).

The reason of the failure was apparent flaw in that a pointer to an uninitialized buffer was
passed to DBUG_PRINT of Protocol_text::store().

Fixed with splitting the print-out into two branches: 
one with length zero of the problematic arg and the rest.

            myisam tables

Queries following TRUNCATE of partitioned MyISAM table
may crash server if myisam_use_mmap is true.

Internally this is MyISAM bug, but limited to partitioned
tables, because MyISAM doesn't use ::delete_all_rows()
method for TRUNCATE, but goes via table recreate instead.

MyISAM didn't properly fall back to non-mmaped I/O after
mmap() failure. Was not repeatable on linux before, likely
because (quote from man mmap):
  SUSv3  specifies  that  mmap() should fail if length is 0.
  However, in kernels before 2.6.12, mmap() succeeded in
  this case: no mapping was created and the call returned
  addr. Since kernel 2.6.12, mmap() fails with the error
  EINVAL for this case.

Problem: caseup_multiply and casedn_multiply members      
were not initialized for a dynamic collation, so          
UPPER() and LOWER() functions returned empty strings.      
Fix: initializing the members properly.

Adding tests:
  mysql-test/r/ctype_ldml.result
  mysql-test/t/ctype_ldml.test

Applying the fix:
  mysys/charset.c

           for InnoDB

Patch to fix result files for the binlog suite under row-
based replication.

Bug #49910: Behavioural change in SELECT/WHERE on YEAR(4) data type                                  
(Original patch by Sinisa Milivojevic)

The YEAR(4) value of 2000 was equal to the "bad" YEAR(4) value of 0000.                              

The get_year_value() function has been modified to not adjust bad                                    
YEAR(4) value to 2000.

comments to rpl_show_slave_running test are added to ease merging

The problem is that when we make conditon for
grouped result const part of condition is cut off.
It happens because some parts of 'having' condition
which refer to outer join become const after
make_join_statistics. These parts may be lost
during further having condition transformation
in JOIN::exec. The fix is adding 'having'
condition check for const tables after
make_join_statistics is performed.

DBUG_SYNC_POINT has at least one strong limitation that it's not defined
on all platforms. It has issues cooperating with @@debug.
All in all its functionality is superseded by DEBUG_SYNC facility and
there is no reason to maintain the old less flexible one.

Fixed with adding debug_sync_set_action() function as a facility to set up
a sync-action in the server sources code and re-writing existing simulations
(found 3) to use it.
Couple of tests have been reworked as well.

The patch offers a pattern for setting sync-points in replication threads
where the standard DEBUG_SYNC does not suffice to reach goals.

This has been back-ported from 6.0 as the problems proved to afflict 
5.1 as well.
The fix exposed two new bugs. They were reported as follows.
      
Bug no 52174: Sometimes wrong plan when reading a MAX value 
from non-NULL index
      
Bug no 52173: Reading NULL value from non-NULL index gives wrong 
result in embedded server 
      
Both bugs taken together affect a much smaller class of queries than #47762, 
so the fix stays for now.