Item*) at opt_sum.cc:305
      
Queries applying MIN/MAX functions to indexed columns are
optimized to read directly from the index if all key parts
of the index preceding the aggregated key part are bound to
constants by the WHERE clause. A prefix length is also
produced, equal to the total length of the bound key
parts. If the aggregated column itself is bound to a
constant, however, it is also included in the prefix.

Such full search keys are read as closed intervals for
reasons beyond the scope of this bug. However, the procedure
missed one case where a key part meant for use as range
endpoint was being overwritten with a NULL value destined
for equality checking. In this case the key part was
overwritten but the range flag remained, causing open
interval reading to be performed.

Bug was fixed by adding more stringent checking to the
search key building procedure (matching_cond) and never
allow overwrites of range predicates with non-range
predicates.

An assertion was added to make sure open intervals are never
used with full search keys.

            strict aliasing violations.

One somewhat major source of strict-aliasing violations and
related warnings is the SQL_LIST structure. For example,
consider its member function `link_in_list` which takes
a pointer to pointer of type T (any type) as a pointer to
pointer to unsigned char. Dereferencing this pointer, which
is done to reset the next field, violates strict-aliasing
rules and might cause problems for surrounding code that
uses the next field of the object being added to the list.

The solution is to use templates to parametrize the SQL_LIST
structure in order to deference the pointers with compatible
types. As a side bonus, it becomes possible to remove quite
a few casts related to acessing data members of SQL_LIST.

           strict aliasing violations.

Essentially, the problem is that large parts of the server were
developed in simpler times (last decades, pre C99 standard) when
strict aliasing and compilers supporting such optimizations were
rare to non-existent. Thus, when compiling the server with a modern
compiler that uses strict aliasing rules to perform optimizations,
there are several places in the code that might trigger undefined
behavior.

As evinced by some recent bugs, GCC does a somewhat good of job
misoptimizing such code, but on the other hand also gives warnings
about suspicious code. One problem is that the warnings aren't
always accurate, yet we can't afford to just shut them off as we
might miss real cases. False-positive cases are aggravated mostly
by casts that are likely to trigger undefined behavior.

The solution is to start a cleanup process focused on fixing and
reducing the amount of strict-aliasing related warnings produced
by GCC and others compilers. A good deal of noise reduction can
be achieved by just removing useless casts that are product of
historical cruft and are likely to trigger undefined behavior if
dereferenced.

Revision ID of the patch: marc.alff@oracle.com-20100608124148-lr1ult7lwo75niev

text conflict: unittest/examples/Makefile.am

The bug was caused by buffered output. Flushing resolved it.
We still recommend to allways call plan().
  
Also fix some compile warnings (formal parameter different from declaration)

Addendum: Work around a compilation failure on Windows due to
          windows.h not being added to the global namespace.

The problem was that the bundled yaSSL library was being built
without thread safety support regardless of the thread safeness
of the compoments linked with it.

The solution is to enable yaSSL thread safety support if any
component (server or client) is to be built with thread support.

Also, generate new certificates for yaSSL's test suite.

Prior to this fix, mysys mutexes such as THR_LOCK_lock could be initialized
twice by a call to my_init().
The root cause was out of place initialization in my_basic_init(),
calling my_thread_global_init().

With this fix,
- my_basic_init() properly initializes the mutex implementation itself,
for SAFE or FAST mutexes, and for platform dependent initializations,
before initialiazing a mutex.
- my_init() properly initializes mysys mutexes once,
when making the first call to my_thread_global_init().

Fixed the failing sys_vars.timestamp_basic.test by 
not re-calculating the value of the system variable at
check time.

Logging slow stored procedures caused the slow log to write 
very large lock times. The lock times was a result of a 
negative number being cast to an unsigned integer.
The reason the lock time appeard negative was because 
one of the measurements points was reset after execution
causing it to change order with the start time of the 
statement.
      
This bug is related to bug 47905 which in turn was 
introduced because of a joint fix for 12480,12481,12482 and 11587.

The fix is to only reset the start_time before any statement
execution in a SP while not resetting start_utime or
utime_after_lock which are used for measuring the 
performance of the SP. Start_time is used to set the
timestamp on the replication event which controlls how
the slave interprets time functions like NOW().

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.

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.

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

            
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.