Fix warnings flagged by the new warning option -Wunused-but-set-variable
that was added to GCC 4.6 and that is enabled by -Wunused and -Wall. The
option causes a warning whenever a local variable is assigned to but is
later unused. It also warns about meaningless pointer dereferences.

client/mysql.cc:
  Meaningless pointer dereferences.
client/mysql_upgrade.c:
  Check whether reading from the file succeeded.
extra/comp_err.c:
  Unused.
extra/yassl/src/yassl_imp.cpp:
  Skip instead of reading data that is discarded.
include/my_pthread.h:
  Variable is only used in debug builds.
include/mysys_err.h:
  Add new error messages.
mysys/errors.c:
  Add new error message for permission related functions.
mysys/mf_iocache.c:
  Variable is only checked under THREAD.
mysys/my_copy.c:
  Raise a error if chmod or chown fails.
mysys/my_redel.c:
  Raise a error if chmod or chown fails.
regex/engine.c:
  Use a equivalent variable for the assert.
server-tools/instance-manager/instance_options.cc:
  Unused.
sql/field.cc:
  Unused.
sql/item.cc:
  Unused.
sql/log.cc:
  Do not ignore the return value of freopen: only set buffer if
  reopening succeeds.
  
  Adjust doxygen comment to the right function.
  
  Pass message lenght to log function.
sql/mysqld.cc:
  Do not ignore the return value of freopen: only set buffer if
  reopening succeeds.
sql/partition_info.cc:
  Unused.
sql/slave.cc:
  No need to set pointer to the address of '\0'.
sql/spatial.cc:
  Unused. Left for historical purposes.
sql/sql_acl.cc:
  Unused.
sql/sql_base.cc:
  Pointers are always set to the same variables.
sql/sql_parse.cc:
  End statement if reading fails.
  
  Store the buffer after it has actually been updated.
sql/sql_repl.cc:
  No need to set pointer to the address of '\0'.
sql/sql_show.cc:
  Put variable under the same ifdef block.
sql/udf_example.c:
  Set null pointer flag appropriately.
storage/csv/ha_tina.cc:
  Meaningless dereferences.
storage/example/ha_example.cc:
  Return the error since it's available.
storage/myisam/mi_locking.c:
  Remove unused and dead code.

           due to GCC preprocessor change
      
The problem is that newer GCC versions treats missing headers
as fatal errors. The solution is to use a guard macro to prevent
the inclusion of system headers when checking the ABI with the
C Preprocessor.

Reference: http://gcc.gnu.org/bugzilla/show_bug.cgi?id=15638
           http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44836

Makefile.am:
  Define guard macro.
configure.in:
  Remove workaround.
include/mysql.h:
  Guard the header inclusion.
include/mysql.h.pp:
  Header is not included anymore.

           table with active trx

Essentially, the problem is that InnoDB does a implicit commit
when a cursor (table handler) is unlocked/closed, creating
a dissonance between the transaction state within the server
layer and the storage engine layer. Theoretically, a statement
transaction can encompass several table instances in a similar
manner to a multiple statement transaction, hence it does not
make sense to limit a statement transaction to the lifetime of
the table instances (cursors) used within it.

Since this particular instance of the problem is only triggerable
on 5.1 and is masked on 5.5 due 2PC being skipped (assertion is in
the prepare phase of a 2PC), the solution (which is less risky) is
to explicitly end the transaction before the cached table is unlock
on rename table.

The patch is to be null merged into trunk.

mysql-test/include/commit.inc:
  Fix counters, the binlog engine does not get involved anymore.
mysql-test/suite/innodb_plugin/r/innodb_bug54453.result:
  Add test case result for Bug#54453
mysql-test/suite/innodb_plugin/t/innodb_bug54453.test:
  Add test case for Bug#54453
sql/sql_table.cc:
  End transaction as otherwise InnoDB will end it behind our backs.

This assert checks that the server does not try to send OK to the
client if there has been some error during processing. This is done
to make sure that the error is in fact sent to the client.

The problem was that view errors during processing of WHERE conditions
in UPDATE statements where not detected by the update code. It therefore
tried to send OK to the client, triggering the assert.
The bug was only noticeable in debug builds.

This patch fixes the problem by making sure that the update code
checks for errors during condition processing and acts accordingly.

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

Backport patch for Bug#47139

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.


libmysqld/examples/Makefile.am:
  Fix for bug #50667: The InnoDB plugin prevents initialization
  of the "embedded" server
    - use -export-dynamic (on FreeBSD/DragonFly) building
  mysqltest_embedded to allow using its global symbols 
  to resolve references in the dynamically loaded plugin libraries.

           compiler problem

GCC-style inline assembly is not supported by the Sun Studio
compilers prior to version 12.

Added a check for the Sun Studio version to avoid using 
_FPU_GETCW() / _FPU_SETCW() when inline assembly is
 unsupported. This can lead to some differences in floating
point calculations on Solaris 8/x86 which, however, is not worth
bothering with Sun-style assembly .il templates.

of autoconf and is not strictly needed for now.

Although the C standard mandates that sprintf return the number
of bytes written, some very ancient systems (i.e. SunOS 4)
returned a pointer to the buffer instead. Since these systems
are not supported anymore and are hopefully long dead by now,
simply remove the portability wrapper that dealt with this
discrepancy. The autoconf check was causing trouble with GCC.

Introduce a MySQL maintainer/developer mode that enables
a set of warning options for the C/C++ compiler. This mode
is intended to help improve the overall quality of the code.

The warning options are:

C_WARNINGS="-Wall -Wextra -Wunused -Wwrite-strings -Werror"
CXX_WARNINGS="$C_WARNINGS -Wno-unused-parameter"

Since -Wall is essentially a moving target, autoconf checks
are not run with warning options enabled, in particualr -Werror.
This decision might be revisited in the future. The patch also
fixes a mistake in the makefiles, where automake CXXFLAGS would
be set to CFLAGS.

config/ac-macros/maintainer.m4:
  Add a set of default compiler flags used when in maintainer mode.
configure.in:
  Hook into the maintainer mode. Disabled by default.

In bug-28430 HA_PRIMARY_KEY_REQUIRED_FOR_POSITION
was disabled in the partitioning engine in the first patch,
That bug was later fixed a second time, but that flag
was not removed.

No need to disable this flag, as it leads to bad
choise in row replication.

sql/ha_partition.h:
  Not disabling HA_PRIMARY_KEY_REQUIRED_FOR_POSITION flag.
  Updated comment (has nothing to do with hidden key.
sql/handler.h:
  Updated comments to about HA_PRIMARY_KEY_REQUIRED_FOR_POSITION.

The problem there is that HAVING condition evaluates const
parts of condition despite the condition has references
on aggregate functions. Table t1 became const tables
after make_join_statistics and table1.pk = 1, HAVING is
transformed into MAX(1) < 7 and taken away from HAVING.
The fix is to skip evaluation of HAVING conts parts if
HAVING condition has references on aggregate functions.


mysql-test/r/having.result:
  test case
mysql-test/t/having.test:
  test case
sql/sql_select.cc:
  skip evaluation of HAVING conts parts if
  HAVING condition has references on aggregate functions.

The handler function for reading one row from a specific index
was not optimized in the partitioning handler since it
used the default implementation.

No test case since it is performance only, verified by hand.

sql/ha_partition.cc:
  Implemented a optimized version of index_read_idx_map
  for the case when find flag == HA_READ_KEY_EXACT,
  which is the common case.
sql/ha_partition.h:
  Declared ha_partition::index_read_idx_map

Fix the memory leak

was not complete. Bootstrap failed to pick up necessary files needed by test and hence
all tests failed.

Since the original fix for this bug lowercases the search pattern it's not a 
good idea to copy the search pattern to the output instead of the real table 
name found (since, depending on the case mode these two names may differ in 
case).
Fixed the infrmation_schema.test failure by making sure the actual table 
name of an inoformation schema table is passed instead of the lookup pattern
even when the pattern doesn't contain wildcards.

           due to GCC preprocessor change

Temporary workaround: disable abi_check if GCC >= 4.5

The atomic operations implementation on 5.1 has a few problems,
which might cause tests to abort randomly. Since no code in 5.1
uses atomic operations, simply remove the code.

Merge up to sunny.bains@oracle.com-20100625081841-ppulnkjk1qlazh82 .
There are 8 more changesets in mysql-5.1-innodb, but PB2 shows a
failure for a test added in one of them. If that is resolved quickly
then those 8 more changesets will be merged too.

Fixed an incomplete historical ALTER TABLE MODIFY trimming the trigger 
privilege bit from mysql.tables_priv.Table_priv column.
Removed the duplicate ALTER TABLE MODIFY.
Test suite added.