Bug#47139: Test "merge" crashes in "embedded" run

Backport patch for Bug#47139

Backport from mysql-next-mr (5.6) to mysql-trunk (5.5)

Backport from mysql-next-mr (5.6) to mysql-trunk (5.5)

Backport from mysql-next-mr (5.6) to mysql-trunk (5.5)

Backport from mysql-next-mr (5.6) to mysql-trunk (5.5)

Backport from mysql-next-mr (5.6) to mysql-trunk (5.5)

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.

Backport from mysql-next-mr (5.6) to mysql-trunk (5.5)

Backport from mysql-next-mr (5.6) to mysql-trunk (5.5)

Backport from mysql-next-mr (5.6) to mysql-trunk (5.5)

Backport from mysql-next-mr (5.6) to mysql-trunk (5.5)

Backporting the fix from myql-next-mr (5.6) to mysql-trunk (5.5)

This fix is for cleanup, to resolve a remaining code review item.
Backport from mysql-next-mr (5.6) to mysql-trunk (5.5).

Fixed minor merge issues with #includes

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.