Revert "MDEV-24454 Crash at change_item_tree"

This patch reverts the fixes of the bugs MDEV-24454 and MDEV-25631 from
the commit 3690c549.
It leaves the changes in plugin/feedback/feedback.cc and corresponding
test files introduced in this commit intact.

Proper fixes for the bug MDEV-24454 and MDEV-25631 will follow immediately.

mysql-test/r/view.result

@@ -6833,49 +6833,6 @@ sum(z)
 DROP TABLE t1;
 DROP VIEW v1;
 #
-# MDEV-24454: Crash at change_item_tree
-#
-CREATE TABLE t1(f0 INT);
-CREATE VIEW v1 AS
-SELECT
-f0 AS f1
-FROM t1;
-CREATE VIEW v2 AS
-SELECT
-(SELECT GROUP_CONCAT(v1.f1 SEPARATOR ', ')
-FROM v1 n) AS f2,
-GROUP_CONCAT('' SEPARATOR ', ') AS f3
-FROM v1;
-CREATE VIEW v3 AS
-SELECT 1 as f4 FROM v2;
-CREATE PROCEDURE p1()
-SELECT * FROM v3;
-CALL p1();
-f4
-1
-CALL p1();
-f4
-1
-drop procedure p1;
-drop view v1,v2,v3;
-drop table t1;
-#
-# MDEV-25631: Crash in st_select_lex::mark_as_dependent with
-# VIEW, aggregate and subquery
-#
-CREATE TABLE t1 (i1 int);
-insert into t1 values (1),(2),(3);
-CREATE VIEW v1 AS
-SELECT t1.i1 FROM (t1 a JOIN t1 ON (t1.i1 = (SELECT t1.i1 FROM t1 b)));
-SELECT 1 FROM (SELECT count(((SELECT i1 FROM v1))) FROM v1) dt ;
-ERROR 21000: Subquery returns more than 1 row
-delete from t1 where i1 > 1;
-SELECT 1 FROM (SELECT count(((SELECT i1 FROM v1))) FROM v1) dt ;
-1
-1
-drop view v1;
-drop table t1;
-#
 # MDEV-26299: Some views force server (and mysqldump) to generate
 # invalid SQL for their definitions
 #

mysql-test/t/view.test

@@ -6559,56 +6559,6 @@ SELECT sum(z) FROM v1;
 DROP TABLE t1;
 DROP VIEW v1;
 
---echo #
---echo # MDEV-24454: Crash at change_item_tree
---echo #
-
-CREATE TABLE t1(f0 INT);
-
-CREATE VIEW v1 AS
-SELECT
-  f0 AS f1
-FROM t1;
-
-CREATE VIEW v2 AS
-SELECT
-  (SELECT GROUP_CONCAT(v1.f1 SEPARATOR ', ')
-   FROM v1 n) AS f2,
-  GROUP_CONCAT('' SEPARATOR ', ') AS f3
-FROM v1;
-
-CREATE VIEW v3 AS
-SELECT 1 as f4 FROM v2;
-
-CREATE PROCEDURE p1()
-  SELECT * FROM v3;
-
-CALL p1();
-CALL p1();
-
-drop procedure p1;
-drop view v1,v2,v3;
-drop table t1;
-
---echo #
---echo # MDEV-25631: Crash in st_select_lex::mark_as_dependent with
---echo # VIEW, aggregate and subquery
---echo #
-
-CREATE TABLE t1 (i1 int);
-insert into t1 values (1),(2),(3); #not important
-CREATE VIEW v1 AS
-	SELECT t1.i1 FROM (t1 a JOIN t1 ON (t1.i1 = (SELECT t1.i1 FROM t1 b)));
-
---error ER_SUBQUERY_NO_1_ROW
-SELECT 1 FROM (SELECT count(((SELECT i1 FROM v1))) FROM v1) dt ;
-delete from t1 where i1 > 1;
-SELECT 1 FROM (SELECT count(((SELECT i1 FROM v1))) FROM v1) dt ;
-
-drop view v1;
-drop table t1;
-
-
 --echo #
 --echo # MDEV-26299: Some views force server (and mysqldump) to generate
 --echo # invalid SQL for their definitions

sql/item.h

@@ -2630,7 +2630,6 @@ class Item_ident :public Item_result_field
     Collect outer references
   */
   virtual bool collect_outer_ref_processor(void *arg);
-  Item *derived_field_transformer_for_having(THD *thd, uchar *arg);
   friend bool insert_fields(THD *thd, Name_resolution_context *context,
                             const char *db_name,
                             const char *table_name, List_iterator<Item> *it,

sql/item_subselect.cc

@@ -5190,9 +5190,8 @@ bool subselect_hash_sj_engine::make_semi_join_conds()
                                 NULL, TL_READ);
   tmp_table_ref->table= tmp_table;
 
-  context= new (thd->mem_root) Name_resolution_context;
+  context= new Name_resolution_context;
   context->init();
-  context->select_lex= item_in->unit->first_select();
   context->first_name_resolution_table=
     context->last_name_resolution_table= tmp_table_ref;
   semi_join_conds_context= context;

sql/item_sum.cc

@@ -68,7 +68,6 @@ size_t Item_sum::ram_limitation(THD *thd)
 bool Item_sum::init_sum_func_check(THD *thd)
 {
   SELECT_LEX *curr_sel= thd->lex->current_select;
-  LEX *lex_s= (curr_sel ? curr_sel->parent_lex : thd->lex);
   if (curr_sel && !curr_sel->name_visibility_map)
   {
     for (SELECT_LEX *sl= curr_sel; sl; sl= sl->context.outer_select())
@@ -83,9 +82,9 @@ bool Item_sum::init_sum_func_check(THD *thd)
     return TRUE;
   }
   /* Set a reference to the nesting set function if there is  any */
-  in_sum_func= lex_s->in_sum_func;
+  in_sum_func= thd->lex->in_sum_func;
   /* Save a pointer to object to be used in items for nested set functions */
-  lex_s->in_sum_func= this;
+  thd->lex->in_sum_func= this;
   nest_level= thd->lex->current_select->nest_level;
   ref_by= 0;
   aggr_level= -1;
@@ -152,7 +151,6 @@ bool Item_sum::init_sum_func_check(THD *thd)
 bool Item_sum::check_sum_func(THD *thd, Item **ref)
 {
   SELECT_LEX *curr_sel= thd->lex->current_select;
-  LEX *lex_s= curr_sel->parent_lex;
   nesting_map allow_sum_func= (thd->lex->allow_sum_func &
                                curr_sel->name_visibility_map);
   bool invalid= FALSE;
@@ -312,7 +310,7 @@ bool Item_sum::check_sum_func(THD *thd, Item **ref)
   }
   aggr_sel->set_agg_func_used(true);
   update_used_tables();
-  lex_s->in_sum_func= in_sum_func;
+  thd->lex->in_sum_func= in_sum_func;
   return FALSE;
 }
 

sql/sql_base.cc

@@ -6440,7 +6440,6 @@ set_new_item_local_context(THD *thd, Item_ident *item, TABLE_LIST *table_ref)
   if (!(context= new (thd->mem_root) Name_resolution_context))
     return TRUE;
   context->init();
-  context->select_lex= table_ref->select_lex;
   context->first_name_resolution_table=
     context->last_name_resolution_table= table_ref;
   item->context= context;

sql/sql_prepare.cc

@@ -3060,7 +3060,6 @@ void reinit_stmt_before_use(THD *thd, LEX *lex)
   }
   for (; sl; sl= sl->next_select_in_list())
   {
-    sl->parent_lex->in_sum_func= NULL;
     if (sl->changed_elements & TOUCHED_SEL_COND)
     {
       /* remove option which was put by mysql_explain_union() */
@@ -3191,6 +3190,7 @@ void reinit_stmt_before_use(THD *thd, LEX *lex)
     lex->result->set_thd(thd);
   }
   lex->allow_sum_func= 0;
+  lex->in_sum_func= NULL;
   DBUG_VOID_RETURN;
 }