azio didn't handle situation when my_read() returns error.

Added handling of situation when my_read() returns error.

No test case for this fix.

into  stella.local:/home2/mydev/mysql-5.1-axmrg

into  stella.local:/home2/mydev/mysql-5.1-axmrg

into  stella.local:/home2/mydev/mysql-5.1-axmrg

into  stella.local:/home2/mydev/mysql-5.0-axmrg

into  stella.local:/home2/mydev/mysql-5.1-axmrg

into  stella.local:/home2/mydev/mysql-5.1-axmrg

into  stella.local:/home2/mydev/mysql-5.1-axmrg

into  pippilotta.erinye.com:/shared/home/df/mysql/build/mysql-5.1

into  stella.local:/home2/mydev/mysql-5.0-axmrg

The patch for Bug 26379 (Combination of FLUSH TABLE and
REPAIR TABLE corrupts a MERGE table) fixed this bug too.
However it revealed a new bug that crashed the server.

Flushing a merge table at the moment when it is between open
and attach of children crashed the server.

The flushing thread wants to abort locks on the flushed table.
It calls ha_myisammrg::lock_count() and ha_myisammrg::store_lock()
on the TABLE object of the other thread.

Changed ha_myisammrg::lock_count() and ha_myisammrg::store_lock()
to accept non-attached children. ha_myisammrg::lock_count() returns
the number of MyISAM tables in the MERGE table so that the memory
allocation done by get_lock_data() is done correctly, even if the
children become attached before ha_myisammrg::store_lock() is
called. ha_myisammrg::store_lock() will not return any lock if the
children are not attached.

This is however a change in the handler interface. lock_count()
can now return a higher number than store_lock() stores locks.
This is more safe than the reverse implementation would be.
get_lock_data() in the SQL layer is adjusted accordingly. It sets
MYSQL_LOCK::lock_count based on the number of locks returned by
the handler::store_lock() calls, not based on the numbers returned
by the handler::lock_count() calls. The latter are only used for
allocation of memory now.

No test case. The test suite cannot reliably run FLUSH between
lock_count() and store_lock() of another thread. The bug report
contains a program that can repeat the problem with some
probability.

into  witty.:/Users/mattiasj/clones/51_push32948

into  pippilotta.erinye.com:/shared/home/df/mysql/build/mysql-5.1-build

into  pippilotta.erinye.com:/shared/home/df/mysql/build/mysql-5.0-build

into  pippilotta.erinye.com:/shared/home/df/mysql/build/mysql-5.1-build

into  pippilotta.erinye.com:/shared/home/df/mysql/build/mysql-5.0-build

into  pippilotta.erinye.com:/shared/home/df/mysql/build/mysql-5.1-build

into  pippilotta.erinye.com:/shared/home/df/mysql/build/mysql-5.0-build

into  pippilotta.erinye.com:/shared/home/df/mysql/build/mysql-4.1-build

Change LAST_EXECUTED time the execution start time, instead of the execution completion time. This ensures the END time always the same or later than the LAST_EXECUTED time.

into  ramayana.hindu.god:/home/tsmith/m/bk/maint/51

into  five.local.lan:/work/merge/mysql-5.1-build-parts

into  trift2.:/MySQL/M51/push-5.1

    Makefile syntax error, comment should precede the whole target.

into  trift2.:/MySQL/M51/push-5.1

into  trift2.:/MySQL/M50/push-5.0

into  trift2.:/MySQL/M51/push-5.1

into  trift2.:/MySQL/M51/push-5.1

into  ramayana.hindu.god:/home/tsmith/m/bk/maint/51

into  ramayana.hindu.god:/home/tsmith/m/bk/maint/51

    In the "test-bt" target, replace the call "$(MAKE) test-embedded" by the actions of that target.

into  ramayana.hindu.god:/home/tsmith/m/bk/maint/50

            with error 1005.

CSV doesn't support nullable fields. Report descriptive error if create
table with nullable field is requested.

into  ramayana.hindu.god:/home/tsmith/m/bk/maint/51-merge

into  ramayana.hindu.god:/home/tsmith/m/bk/maint/50

testing embedded server works correctly.