The problem is in the Item_func_isnull::update_used_tables() function,
bracket is at the wrong place. Because of that isnull item erroneously
is treated as const item. The fix is to set brackets in the right place.


mysql-test/r/func_isnull.result:
  test case
mysql-test/t/func_isnull.test:
  test case
sql/item_cmpfunc.h:
  set brackets in the right place.

when an out-of-supported-range date is detected.

Conflicts:
  - BUILD/SETUP.sh
  - mysql-test/mysql-test-run.pl
  - mysql-test/r/partition_error.result
  - mysql-test/t/disabled.def
  - mysql-test/t/partition_error.test
  - sql/share/errmsg-utf8.txt

Also, update a few cases missed by the initial patch.

client/mysqltest.cc:
  Remove trailing comma.
include/my_alloc.h:
  Do not use wrapper.
include/mysql.h.pp:
  Update ABI file.
plugin/semisync/semisync_master.h:
  Initialize variable.
sql/debug_sync.cc:
  Use C linkage.

NET::skip_big_packet isn't defined for the embedded server,
hide it in such a case.


sql/sql_connect.cc:
  Fix for bug #53912: Fails to build from source
    - hide net.skip_big_packet for the embedded server,
  as it isn't defined there.

            
Some of the server implementations don't support dates later
than 2038 due to the internal time type being 32 bit.
Added checks so that the server will refuse dates that cannot
be handled by either throwing an error when setting date at 
runtime or by refusing to start or shutting down the server if 
the system date cannot be stored in my_time_t.

Patch for bug#52913: Inserted check if mysqlhotcopy script is existing as requested by review. DIsabled the test until bug#54129 will befixed.

Post-push fix.

Post-push fix.

  
Post-push fix.
  
There was a valgrind issue on the loop that checks whether there
are NULL fields in the UNIQUE KEY or not. In detail, for the last 
iteration the server may read out of the key_part array boundaries,
making valgrind to output warnings.

We fix this by correcting the loop, ie, moving the part that reads
from the key_part to be inside the loop statement block. This way
the assignment is protected by the loop condition.

When using Unique Keys with nullable parts in RBR, the slave can
choose the wrong row to update. This happens because a table with
an unique key containing nullable parts cannot strictly guarantee 
uniqueness. As stated in the manual, for all engines, a UNIQUE 
index allows multiple NULL values for columns that can contain 
NULL.

We fix this at the slave by extending the checks before assuming
that the row found through an unique index is is the correct
one. This means that when a record (R) is fetched from the storage
engine and a key that is not primary (K) is used, the server does 
the following: 

 - If K is unique and has no nullable parts, it returns R;
 - Otherwise, if any field in the before image that is part of K
   is null do an index scan;
 - If there is no NULL field in the BI part of K, then return R.

A side change: renamed the existing test case file and added a
test case covering the changes in this patch.

MTR will ignore fully qualified test name entries in disabled.def 
lists. Therefore, it would still run the test case, even if it is
listed.

This patch fix this by extending the check when marking the test
case as disabled to take into consideration not only the cases that
contain the simple test name but also those that contain fully 
qualified test names.

conflicts:
   conflict      configure.in

result file differs on embedded

Fix various mismatches between function's language linkage. Any
particular function that is declared in C++ but should be callable
from C must have C linkage. Note that function types with different
linkages are also distinct. Thus, if a function type is declared in
C code, it will have C linkage (same if declared in a extern "C"
block).

client/mysql.cc:
  Mismatch between prototype and declaration.
client/mysqltest.cc:
  mysqltest used to be C code. Use C linkage where appropriate.
cmd-line-utils/readline/input.c:
  Isolate unreachable code.
include/my_alloc.h:
  Function type must have C linkage.
include/my_base.h:
  Function type must have C linkage.
include/my_global.h:
  Add helper macros to avoid spurious namespace indentation.
include/mysql.h.pp:
  Update ABI file.
mysys/my_gethwaddr.c:
  Remove stray carriage return and fix coding style.
plugin/semisync/semisync_master_plugin.cc:
  Callback function types have C linkage.
plugin/semisync/semisync_slave_plugin.cc:
  Callback function types have C linkage.
sql/derror.cc:
  Expected function type has C linkage.
sql/field.cc:
  Use helper macro and fix indentation.
sql/handler.cc:
  Expected function type has C linkage.
sql/item_sum.cc:
  Correct function linkages. Remove now unnecessary cast.
sql/item_sum.h:
  Add prototypes with the appropriate linkage as otherwise they
  are distinct.
sql/mysqld.cc:
  Wrap functions in C linkage mode.
sql/opt_range.cc:
  C language linkage is ignored for class member functions.
sql/partition_info.cc:
  Add wrapper functions with C linkage for class member functions.
sql/rpl_utility.h:
  Use helper macro and fix indentation.
sql/sql_class.cc:
  Change type of thd argument -- THD is a class.
  Use helper macro and fix indentation.
sql/sql_class.h:
  Change type of thd argument -- THD is a class.
sql/sql_select.cc:
  Expected function type has C linkage.
sql/sql_select.h:
  Move prototype to sql_test.h
sql/sql_show.cc:
  Expected function type has C linkage.
sql/sql_test.cc:
  Fix required function prototype and fix coding style.
sql/sql_test.h:
  Removed unnecessary export and add another.
storage/myisammrg/ha_myisammrg.cc:
  Expected function type has C linkage.
storage/perfschema/pfs.cc:
  PSI headers are declared with C language linkage, which also
  applies to function types.