Improve previous push: save 1000 bytes of thread stack in non-error cases

  If MySQL tries to do SELECT from an InnoDB table, but has set no table locks at all in ::external_lock(), print a descriptive error message and assert; some subquery bugs were of this type

into mysql.com:/home/mysql_src/mysql-4.1

mysql_alter_db() now returns -1 in case of error, so that mysql_execute_command()
calls send_error().

into serg.mylan:/usr/home/serg/Abk/mysql-4.1-bug

checking 2nd level of FT index destroyed info->lastkey and CHECK TABLE erroneously treated table as corrupted
bug#2190

  Fixed: client crashed when there are no Index.xml file.

This way, a crash of mysqltest will be visible in the test logs
(output of mysql-test-run).

  Fix typo

Now we return user@host for USER() in embedded library
CURRENT_USER returns empty string if library compiled with
NO_EMBEDDED_ACCESS_CHECKS

WL#1246 (Query cache in embedded library)
Some fixes after testing

WL#1246 (Query cache in embedded library)
Small fix - code removed that prevents using query cache in embedded library

  More instructions about a downgrade 4.1.1 -> 4.0.18

  Add comment that the insert buffer format changed between 4.0 and 4.1.1, but the undo log format did not

  Merge a log replay change required by ibbackup

  Fix bug: if purge of a table was not possible because its .ibd file was missing, trx->dict_operation_lock_mode was left to a wrong value, causing an assertion failure

  Modern Spanish collation

  Logging to logging@openlogging.org accepted
item_strfunc.cc:
  Bug wich appeared in ctype_tis620 is fixed

TIS620 to Unicode and Unicode to TIS620 conversion check.

  new file

  new file

  Fix for the bug 1175: Usernames will not converted to utf8 during connect

  he mysqld server crashes if issued a command select convert(...)
  with a
  non-compiled character set:

  install-test-db did not substiture the path to charsets file, so tests failed with non-default collation incompiled, for example --with-collation=latin1_german1_ci
mysqld.cc:
  better error messaging

into deer.(none):/home/hf/work/mysql-4.1.2046

into teton.kitebird.com:/home/paul/mysql-4.1

into deer.(none):/home/hf/work/mysql-4.1.2181

server)
We didn't perform the check for the error for embedded server

into mysql.com:/home/kostja/mysql/mysql-4.1-prep

There was an error with same function/class member names

broken with recent changes' (attempt 2).
Adding Statement_core is better because:
- set_statement() code is shorter and you don't need to modify it when adding
new members to Statement_core
- a bit faster (you don't have virtual call and don't free_root() twice)
Do that short patch instead in hope that set_statement() will be sooner or
later removed entirely

into teton.kitebird.com:/home/paul/mysql-4.1

into mysql.com:/home/kostja/mysql/mysql-4.1-root