of the "embedded" server

Problem: mysqltest_embedded failed to load ha_innodb_plugin library
on some platforms (due to some unresolved references).

Fix: on FreeBSD use -export-dynamic flag building mysqltest_embedded.
That allows to use its global symbols to resolve references in the
dynamically loaded plugin library.

Post-merge fix: adjust line numbers in pfs_upgrade test case
result given that mysql_system_tables_fix.sql was modified.

mysql_config. Those are mainly warning options intended
to monitor the server code and shouldn't be leaked to
client code.

Silence bogus aliasing warning through a pointer indirection. Also,
no need to check the return of a placement new.

Restore hack necessary to setup a libmysqld archive.

Fix compiler warnings due to: a mismatch in the prototypes for
check_access and implicit conversions from double to ulonglong
and vice-versa.

Remove OS/2 specific code.

Remove QNX specific code.

Remove VMS specific code.

Remove Zortech specific code.

Remove MS-DOS specific code.

Remove Netware specific code.

Calculating the estimated number of records for a range scan
may take a significant time, and it was impossible for a user
to interrupt that process by killing the connection or the
query.

Fixed by checking the thread's 'killed' status in
check_quick_keys() and interrupting the calculation process if
it is set to a non-zero value.

           strict aliasing violations.

Post-merge fix: include my_compiler.h before my_attribute.h
as the latter will undef __attribute__ if the compiler is not
GCC. Based on the compiler version, in my_compiler.h we know
for sure whether the aligned attribute is supported. Furthermore,
undefining attribute might cause bugs if some system header
uses it.

Fixed style according to the specific innodb style, for innodb code.

Backport fixes from ndb: Rework the constructors of some static
object's to not call dbug functions since the constructors will
be called before main, and consequently, before the dbug library
is initialized.

           strict aliasing violations.

Another rather noisy violation of strict aliasing rules
is the spatial code which makes use of stack-based memory
(of type Geometry_buffer) to provide placement for Geometry
objects. Although a placement new is allowed to dynamically
change the type of a object, the object returned by the
new placement was being ignored and the original stack-based
object was being casted to the new type, thus violating strict
aliasing rules.

The solution is to reorganize the code so that the object
returned by the new placement is used instead of casting the
original object. Also, to ensure that the stack-based object
is properly aligned with respect to the objects it provides
placement for, a set of compiler-dependent macros and types
are introduced so that the alignment of objects can be inquired
and specified.

and reverse() function
      
3 problems fixed : 
1. The reported problem : caused by incorrect parsing of 
the file as ucs data resulting in wrong length of the parsed
string. Fixed by truncating the invalid trailing bytes 
(non-complete multibyte characters) when reading from the file
2. LOAD DATA when reading from a proper UCS2 file wasn't 
recognizing the new line characters. Fixed by first looking 
if a byte is a new line (or any other special) character before
reading it as a part of a multibyte character.
3. When using user variables to hold the column data in LOAD
DATA the character set of the user variable was set incorrectly
to the database charset. Fixed by setting it to the charset
specified by LOAD DATA (if any). 

The removal of non-local root users is overzealous in
mysql_secure_installation. (Bug #54004)

bytes_received/bytes_sent are ulonglong so they cannot be handled by the 
ulong handling code in add_to_status/add_diff_to_status().

Fixed by adding code to handle these two variables in 
add_to_status()/add_diff_to_status() and making sure they are not a subject
to the ulong handling code.

Symptom:
When the sql function SLEEP() was executed in the slave SQL thread or from an event (as in
CREATE EVENT, not binlog event), then the timeout was capped to 5 seconds.

Background:
This bug was introduced in the fix of BUG#10374, in the function interruptible_wait() in
item_func.cc.
The function interruptible_wait(), called from item_func_sleep::val_int(), splits the
sleep into 5 seconds units. After each unit, it checks if thd->is_connected() is true: if
not, it stops sleeping. The purpose is to not use system resources to sleep when a client
disconnects.
However, thd->is_connected() returns false for the slave SQL thread and for the event
worker thread, because they don't connect to the server the same way as client threads
do.

Fix:
Make thd->is_connected() return true for all system threads.