end_io_call uses uninitialized values from the new_data_cache
As such we the buffer 0 and check this before calling end_io_cache on it.
Thanks Sergey Vojtovich for the review and for this solution.
Found by Coverity (ref 972481).
A few tests assumes that the CYCLE timer is always available,
which is not true on some platforms (e.g. ARM).
Fixing the tests not to reply on the CYCLE availability.
Coverity report this as:
CID 971840 (#1 of 1): Operands don't affect result (CONSTANT_EXPRESSION_RESULT)
result_independent_of_operands: 4 | (flags & 1) is always true regardless of the values of its operands. This occurs as the logical first operand of "?:".
The C order of precidence has | of higher precidence than ?:. The
intenting implies an | of the 3 terms.
Adjust to intented meaning.
field_names[x][y] is a pointer
client/mysql.cc: In function 'void build_completion_hash(bool, bool)':
client/mysql.cc:2855:37: error: invalid conversion from 'char' to 'char*' [-fpermissive]
field_names[i][num_fields*2]= '\0';
Signed-off-by: Daniel Black <daniel.black@au.ibm.com>
Same MDEV, second bug.
Merge buffer must fit at least MERGEBUFF2 (that is, 15) key values.
Because merge_index() can merge that many buffers, and
merge_many_buff() leaves that many buffers unmerged.
Item_in_subselect::pushed_cond_guards[] array is allocated only when
left_expr->maybe_null. And it is used (for row expressions) when
left_expr->element_index(i)->maybe_null.
For left_expr being a multi-column subquery, its maybe_null is
always false when the subquery doesn't use tables (see
Item_singlerow_subselect::fix_length_and_dec()
and subselect_single_select_engine::fix_length_and_dec()),
otherwise it's always true.
But row elements can be NULL regardless, so let's always allocate
pushed_cond_guards for multi-column subqueries, no matter whether
its maybe_null was forced to true or false.
CID 971836 (#1 of 1): Same on both sides (CONSTANT_EXPRESSION_RESULT)
pointless_expression: The expression val != end && val != end does not
accomplish anything because it evaluates to either of its identical
operands, val != end.
This is actually a legacy bug:
SQL_SELECT::test_quick_select() was called
with SQL_SELECT::head not set.
It looks like that this problem can be
reproduced only on queries with ORDER BY
that use IN predicates converted to semi-joins.
This patch corrects the fix for bug mdev-7599.
When the min/max optimization of the function
opt_sum_query() optimizes away all tables of
a subquery it should not ever be rolled back.
If the optimizer chose an execution plan where
a semi-join nest were materialized and the
result of materialization was scanned to access
other tables by ref access it could build a key
over columns of the tables from the nest that
were actually inaccessible.
The patch performs a proper check whether a key
that uses columns of the tables from a materialized
semi-join nest can be employed to access outer tables.
RPL_SEMI_SYNC_MASTER_CLIENTS=1
Analysis: Uninstalling rpl_semi_sync_slave on slave
will trigger removing the slave logic on Master which
will reduce Rpl_semi_sync_master_clients by one number.
But it happens asynchronously on Master. Having assert
to check this value with zero will have problems on
slow pb2 machines.
Fix: Change assert into wait_for_status_var condition.
