Initialize MYSQL_LOCK->flags variable

This could crash in mysql_unlock_tables in servers compiled with DBUG

Make a test more robust

Sometimes, the test would fail with a result difference for
the READ UNCOMMITTED read, because the incremental backup
would finish before redo log was written for all the rows
that were inserted in the second batch.

To fix that, cause a redo log write by creating another
transaction. The transaction rollback (which internally does commit)
will be flushed to the redo log, and before that, all the preceding
changes will be flushed to the redo log as well.

Additions to the list of unstable tests for 10.2.11

MDEV-14205 Windows : fix race condition writing into error log and se…

…tvbuf

Do not do reopen_fstreams/setbuf twice during server startup on Windows.
fprintf(stderr,..) might crash, if setbuf is executed at the same time.

MW-388

Test uses now debug and debug_sync.

Add a missing space to an error message

List of unstable tests for 10.0.33 release

Fix test failure on perfschema.all_instances.

Bug#26361149 MYSQL SERVER CRASHES AT: COL IN(IFNULL(CONST, COL), NAME…

…_CONST('NAME', NULL))

based on:

commit f7316aa
Author: Ajo Robert <ajo.robert@oracle.com>
Date:   Thu Aug 24 17:03:21 2017 +0530

    Bug#26361149  MYSQL SERVER CRASHES AT: COL IN(IFNULL(CONST,
                           COL), NAME_CONST('NAME', NULL))

    Backport of Bug#19143243 fix.

    NAME_CONST item can return NULL_ITEM type in case of incorrect arguments.
    NULL_ITEM has special processing in Item_func_in function.
    In Item_func_in::fix_length_and_dec an array of possible comparators is
    created. Since NAME_CONST function has NULL_ITEM type, corresponding
    array element is empty. Then NAME_CONST is wrapped to ITEM_CACHE.
    ITEM_CACHE can not return proper type(NULL_ITEM) in Item_func_in::val_int(),
    so the NULL_ITEM is attempted compared with an empty comparator.
    The fix is to disable the caching of Item_name_const item.

fixes for --embedded