A number of after-merge fixes following merge of MySQL 5.1.44 into MariaDB.

Bug#46949: memory leak with failed alter table to create partitions based on extract()

Bug#51830: Incorrect partition pruning on range partition (regression)

Fixed valgrind failure in select_describe(), read of uninitialized 
  Item_subselect::eliminated.

PBXT test file updates to reflect changes done in MySQL.

mysql-test/suite/pbxt/r/partition_error.result:
  Result file update following MySQL 5.1.44 changes.
mysql-test/suite/pbxt/r/partition_pruning.result:
  Result file update following MySQL 5.1.44 changes.
mysql-test/suite/pbxt/t/partition_error.test:
  Test file update following MySQL 5.1.44 changes.
sql/item_subselect.cc:
    Fixed valgrind failure in select_describe(), read of uninitialized 
    Item_subselect::eliminated: 
    - it turns out we can call select_describe() without having fixed 
      subquery items for child subselects. These are not the kind of subqueries
      that we could eliminate, so the fix is to ensure that 
      item_subselect->eliminated==FALSE even before fix_fields is called.
      Also added code to reset item_subselect->eliminated back to FALSE in
      Item::reset() call.
sql/item_subselect.h:
    Fixed valgrind failure in select_describe(), read of uninitialized 
    Item_subselect::eliminated: 
    - it turns out we can call select_describe() without having fixed 
      subquery items for child subselects. These are not the kind of subqueries
      that we could eliminate, so the fix is to ensure that 
      item_subselect->eliminated==FALSE even before fix_fields is called.
      Also added code to reset item_subselect->eliminated back to FALSE in
      Item::reset() call.
sql/sql_partition.cc:
  Fix Bug#51830: Revert part of the patch for Bug#49742, which caused the regression.
sql/table.cc:
  Fix Bug#46949: memory leak in failed ALTER TABLE with partitioning.

1 files changed, 3 insertions, 0 deletions

diff --git a/sql/item_subselect.h b/sql/item_subselect.h
index 50f8885f862..8d43f2bd383 100644
--- a/sql/item_subselect.h
+++ b/sql/item_subselect.h
@@ -90,6 +90,7 @@ public:
   void cleanup();
   virtual void reset()
   {
+    eliminated= FALSE;
     null_value= 1;
   }
   virtual trans_res select_transformer(JOIN *join);
@@ -235,6 +236,7 @@ public:
   subs_type substype() { return EXISTS_SUBS; }
   void reset() 
   {
+    eliminated= FALSE;
     value= 0;
   }
 
@@ -306,6 +308,7 @@ public:
   subs_type substype() { return IN_SUBS; }
   void reset() 
   {
+    eliminated= FALSE;
     value= 0;
     null_value= 0;
     was_null= 0;