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).
- Ported relevant changes from the upstream version to not
break strict-aliasing rules and to fix compiler warnings and
and infinite loops caused by that issue.
- Fixed compilation with Honor_FLT_ROUNDS defined.
- Fixed an unused variable warning.
Destroy the rw-lock object before freeing the memory it is occupying.
If we do not do this, then the mutex that is contained in the rw-lock
object btr_search_latch_temp->mutex gets "freed" and subsequently
mutex_free() from sync_close() hits a mutex whose memory has been
freed and crashes.
Approved by: Heikki (via IRC)
Discussed with: Calvin
- revid:sp1r-svoj@mysql.com/june.mysql.com-20080324111246-00461
- revid:sp1r-svoj@mysql.com/june.mysql.com-20080414125521-40866
BUG#35274 - merge table doesn't need any base tables, gives
error 124 when key accessed
SELECT queries that use index against a merge table with empty
underlying tables list may return with error "Got error 124 from
storage engine".
The problem was that wrong error being returned.
when it should use index
Sometimes the LEFT/RIGHT JOIN with an empty table caused an
unnecessary filesort.
Sample query, where t1.i1 is indexed and t3 is empty:
SELECT t1.*, t2.* FROM t1 JOIN t2 ON t1.i1 = t2.i2
LEFT JOIN t3 ON t2.i2 = t3.i3
ORDER BY t1.i1 LIMIT 5;
The server erroneously used an item of empty outer-joined
table as a common constant of a Item_equal (multi-equivalence
expression).
By the fix for the bug 16590 the constant status of such
an item has been propagated to st_table::const_key_parts
map bits related to other Item_equal argument-related
key parts (those are obviously not constant in our case).
As far as test_if_skip_sort_order function skips constant
prefixes of testing keys, this caused an ignorance of
available indices, since some prefixes were marked as
constant by mistake.
bug #51263 "Deadlock between transactional SELECT and ALTER
TABLE ... REBUILD PARTITION" and has been causing compilation
error when server was built with NDB support.
and .tar.gz, windows vs linux..
On Intel x86 machines index selection by the MySQL query
optimizer could sometimes depend on the compiler version and
optimization flags used to build the server binary.
The problem was a result of a known issue with floating point
calculations on x86: since internal FPU precision (80 bit)
differs from precision used by programs (32-bit float or 64-bit
double), the result of calculating a complex expression may
depend on how FPU registers are allocated by the compiler and
whether intermediate values are spilled from FPU to memory. In
this particular case compiler versions and optimization flags
had an effect on cost calculation when choosing the best index
in best_access_path().
A possible solution to this problem which has already been
implemented in mysql-trunk is to limit FPU internal precision
to 64 bits. So the fix is a backport of the relevant code to
5.1 from mysql-trunk.
The problem is that if a NULL is stored in an Item_cache_decimal object,
the associated my_decimal object is not initialized. However, it is still
accessed when val_int() is called. The fix is to check for null_value
within val_int(), and return without accessing the my_decimal object when
the cached value is NULL.
Bug#52122 reports the same issue for val_real(), and this patch also includes
fixes for val_real() and val_str() and corresponding test cases from that
bug report.
Also, NULL is returned from val_decimal() when value is null. This will
avoid that callers access an uninitialized my_decimal object.
Made similar changes to all other Item_cache classes. Now all val_*
methods should return a well defined value when actual value is NULL.
err_index could be not a member of the share structure or prebuilt
structure passed from MySQL. For now, we resort to the traditional
way of scanning index->table for the index number.
is allowed on views (not documented, broken)".
Remove support of ALTER TABLE RENAME for views as:
a) this feature was not documented,
c) does not add any compatibility with other databases,
b) its implementation doesn't follow metadata locking
protocol by accessing .FRM without holding any
metadata lock,
c) its implementation complicates ALTER TABLE's code
by introducing yet another separate branch to it.
After this patch one can rename a view by using the
documented way - RENAME TABLE statement.
Add code to waiting for a set of errors.
Add code to waiting for an error instead of waiting for io thread to stop, as
after 'START SLAVE', the status of io thread is still not running.
But it doesn't mean slave io thread encounters an error.
Post-merge fix: Pass the right parameter type to open_and_lock_tables.
Passing FALSE ensures that derived table handling is disabled, truncate
only operates on base tables.
without FOR UPDATE is causing a lock".
SELECT statements with subqueries referencing InnoDB tables
were acquiring shared locks on rows in these tables when they
were executed in REPEATABLE-READ mode and with statement or
mixed mode binary logging turned on.
This was a regression which were introduced when fixing
bug 39843.
The problem was that for tables belonging to subqueries
parser set TL_READ_DEFAULT as a lock type. In cases when
statement/mixed binary logging at open_tables() time this
type of lock was converted to TL_READ_NO_INSERT lock at
open_tables() time and caused InnoDB engine to acquire
shared locks on reads from these tables. Although in some
cases such behavior was correct (e.g. for subqueries in
DELETE) in case of SELECT it has caused unnecessary locking.
This patch implements minimal version of the fix for the
specific problem described in the bug-report which supposed
to be not too risky for pushing into 5.1 tree.
The 5.5 tree already contains a more appropriate solution
which also addresses other related issues like bug 53921
"Wrong locks for SELECTs used stored functions may lead
to broken SBR".
This patch tries to solve the problem by ensuring that
TL_READ_DEFAULT lock which is set in the parser for
tables participating in subqueries at open_tables()
time is interpreted as TL_READ_NO_INSERT or TL_READ.
TL_READ is used only if we know that this is a SELECT
and that this particular table is not used by a stored
function.
Test coverage is added for both InnoDB and MyISAM.
This patch introduces an "incompatible" change in locking
scheme for subqueries used in SELECT ... FOR UPDATE and
SELECT .. IN SHARE MODE.
In 4.1 (as well as in 5.0 and 5.1 before fix for bug 39843)
the server would use a snapshot InnoDB read for subqueries
in SELECT FOR UPDATE and SELECT .. IN SHARE MODE statements,
regardless of whether the binary log is on or off.
If the user required a different type of read (i.e. locking
read), he/she could request so explicitly by providing FOR
UPDATE/IN SHARE MODE clause for each individual subquery.
The patch for bug 39843 broke this behaviour (which was not
documented or tested), and started to use locking reads for
all subqueries in SELECT ... FOR UPDATE/IN SHARE MODE.
This patch restores 4.1 behaviour.
This patch should be mostly null-merged into 5.5 tree.
is not needed any more with current versions of FreeBSD.
(Entries 52410 and 52412 in the Bug DB)
That change is based on Dan Nelson replying on the
FreeBSD mailing list, freebsd-questions@freebsd.org
in a thread running from 2010-Apr-29 to 2010-May-1 titled
"Need info about FreeBSD and interrupted system
calls for MySQL code"
Also, ensure the cmake settings correspond to the autotools
ones: Add "HAVE_BROKEN_REALPATH" to cmake.
