Merge conflicts in test "create:
- for "create.result", handled correctly by "bzr extmerge" (using "kdiff3"),
- for "create.test", not reported as a conflict, but merged wrong
  (new block at the test end got duplicated), fixed manually.

Test on Linux (Debian, PowerPC) was ok.

           derived table cause crash

When a multi-UPDATE command fails to lock some table, and
subsequently succeeds, the tables need to be reopened if
they were altered. But the reopening procedure failed for
derived tables.

Extra cleanup has been added.

          ``FLUSH TABLES WITH READ LOCK''

Concurrent execution of 1) multitable update with a
NATURAL/USING join and 2) a such query as "FLUSH TABLES
WITH READ LOCK" or "ALTER TABLE" of updating table led
to a server crash.


The mysql_multi_update_prepare() function call is optimized
to lock updating tables only, so it postpones locking to
the last, and if locking fails, it does cleanup of modified
syntax structures and repeats a query analysis.  However,
that cleanup procedure was incomplete for NATURAL/USING join
syntax data: 1) some Field_item items pointed into freed
table structures, and 2) the TABLE_LIST::join_columns fields
was not reset.

Major change:
  short-living Field *Natural_join_column::table_field has
  been replaced with long-living Item*.

so that if the substitution contains single-quotes, the program will fail.

(no conflicts)

The grep expression that finds a running "mysqld" program fails if the
"mysqld_safe" is running with the same PID.

Now, excise "ps" output that has the word " grep" or "mysqld_safe" in 
it, to be a little more certain that the matched process is not a false 
positive hit.  This will fail when the path to mysqld contains either
of those two names, which should be acceptable.

Additionally, some text to search could be truncated if very long.  
Expand the number of lines "ps" emits.

mysql-test-run.pl --start-and-exit starts but does not exit
Instead, it hangs with ActiveState perl. The error is
believed to be a bug in ActiveState implementation.
Workaround is using POSIX::_exit, as described here
http://www.perlmonks.org/?node_id=334610

Thanks to Philip Stoev for the idea of the patch.

The '@' symbol can not be used in the host name according to rfc952.
The fix:
added function check_host_name(LEX_STRING *str)
which checks that all symbols in host name string are valid and
host name length is not more than max host name length
(just moved check_string_length() function from the parser into check_host_name()).

                  tests "<ENGINE>_func_view" fail

The problem:
I_S views table does not check the presence of SHOW_VIEW_ACL|SELECT_ACL
privileges for a view. It leads to discrepancy between SHOW CREATE VIEW
and I_S.VIEWS.
The fix:
added appropriate check.

            
When analyzing the possible index use cases the server was re-using an internal structure.
This is wrong, as this internal structure gets updated during the analysis.
Fixed by making a copy of the internal structure for every place it needs to be used.
Also stopped the generation of empty SEL_TREE structures that unnecessary 
complicate the analysis.

from stored procedure. 

Problem: we replace all references to local variables in stored procedures     
with NAME_CONST(name, value) logging to the binary log. However, if the
value's collation differs we might get an 'illegal mix of collation'           
error as we don't pass the collation to the function.

Fix: pass the value's collation to NAME_CONST().

Note: actually we should pass to NAME_CONST() the value's derivation as well.
It's impossible without the parser modifying. Now we always set the 
derivation to DERIVATION_IMPLICIT, the same as local variables have.

Repush of change to fix tests on Pushbuild.

Server created "arc" directories inside database directories and
maintained there useless copies of .frm files.

Creation and renaming procedures of those copies as well as
creation of "arc" directories has been discontinued.
Removal procedure has been kept untouched to be able to
cleanup existent database directories by the DROP DATABASE
query. Also view renaming procedure has been updated to remove
these directories.

     JOIN for the subselect wasn't cleaned if we came upon an error
     during sub_select() execution. That leads to the assertion failure
     in close_thread_tables()

     part of the 6.0 code backported

per-file comments:
  mysql-test/r/sp-error.result
Bug#37949 Crash if argument to SP is a subquery that returns more than one row 
    test result

  mysql-test/t/sp-error.test
Bug#37949 Crash if argument to SP is a subquery that returns more than one row 
    test case

  sql/sp_head.cc
Bug#37949 Crash if argument to SP is a subquery that returns more than one row 
    lex->unit.cleanup() call added if not substatement

Machines with hostname set to "localhost" cause uniqueness errors in 
the SQL bootstrap data.

Now, insert zero lines for cases where the (lowercased) hostname is 
the same as an already-inserted 'localhost' name.  Also, fix a few tests 
that expect certain local accounts to have a certain host name.

Bug#38311 - Fix of some cruft from remove_files in ndb_autodiscover.test, clean up of distinct.test,
and replacing error numbers with error names.

            
A stored procedure involving substrings could crash the server on certain
platforms because of invalid memory reads.
          
During storing the new blob-field value, the cached value's address range
overlapped that of the new field value. This caused problems when the 
cached value storage was reallocated to provide access for a new 
characater set representation. The patch checks the address ranges, and if
they overlap, the new field value is copied to a new storage before it is
converted to the new character set.

Substituted use of MTR's remove_file function in the tests
Started with 5.0 tree and will clean up any offenders discovered during upmerge.