Major rehacking and cleanup of sp_pcontext.

This finishes (almost) WL#2002: Implement stored procedure GOTO.
Only the syntax issue for free labels remains ("label L;" vs "L:").

include/mysqld_error.h

@@ -373,4 +373,5 @@
 #define ER_WARN_VIEW_WITHOUT_KEY 1354
 #define ER_VIEW_INVALID 1355
 #define ER_SP_NO_DROP_SP 1356
+#define ER_SP_GOTO_IN_HNDLR 1357
 #define ER_ERROR_MESSAGES 357

mysql-test/r/sp-error.result

@@ -68,6 +68,42 @@ goto foo;
 end|
 ERROR 42000: GOTO with no matching label: foo
 create procedure foo()
+begin
+begin
+label foo;
+end;
+goto foo;
+end|
+ERROR 42000: GOTO with no matching label: foo
+create procedure foo()
+begin
+goto foo;
+begin
+label foo;
+end;
+end|
+ERROR 42000: GOTO with no matching label: foo
+create procedure foo()
+begin
+begin
+goto foo;
+end;
+begin
+label foo;
+end;
+end|
+ERROR 42000: GOTO with no matching label: foo
+create procedure foo()
+begin
+begin
+label foo;
+end;
+begin
+goto foo;
+end;
+end|
+ERROR 42000: GOTO with no matching label: foo
+create procedure foo()
 foo: loop
 foo: loop
 set @x=2;
@@ -288,6 +324,16 @@ declare continue handler for sqlstate '42S99' set x = 1;
 declare c cursor for select * from t1;
 end|
 ERROR 42000: Cursor declaration after handler declaration
+create procedure p()
+begin
+declare continue handler for sqlexception
+begin
+goto L1;
+end;
+select field from t1;
+label L1;
+end|
+ERROR HY000: GOTO is not allowed in a stored procedure handler
 create procedure bug1965()
 begin
 declare c cursor for select val from t1 order by valname;

mysql-test/r/sp.result

-reset master;
 use test;
 drop table if exists t1;
 drop table if exists t2;
@@ -398,7 +397,7 @@ id	data
 i	3
 delete from t1|
 drop procedure i|
-create procedure j()
+create procedure goto1()
 begin
 declare y int;
 label a;
@@ -411,7 +410,7 @@ insert into t1 values ("j", y);
 goto a;
 label b;
 end|
-call j()|
+call goto1()|
 id	data
 id	data
 j	0
@@ -422,8 +421,8 @@ id	data
 j	0
 j	1
 j	2
-drop procedure j|
-create procedure k(a int)
+drop procedure goto1|
+create procedure goto2(a int)
 begin
 declare x int default 0;
 declare continue handler for sqlstate '42S98' set x = 1;
@@ -446,7 +445,7 @@ end;
 end while b;
 select * from t1;
 end|
-call k(0)|
+call goto2(0)|
 id	data
 j	0
 j	1
@@ -455,7 +454,7 @@ id	data
 j	0
 j	1
 j	2
-call k(1)|
+call goto2(1)|
 id	data
 j	0
 j	1
@@ -464,7 +463,7 @@ id	data
 j	0
 j	1
 j	2
-call k(2)|
+call goto2(2)|
 id	data
 j	0
 j	1
@@ -477,8 +476,60 @@ id	data
 j	0
 j	1
 j	2
-drop procedure k|
+drop procedure goto2|
 delete from t1|
+create procedure goto3()
+begin
+label L1;
+begin
+end;
+goto L1;
+end|
+drop procedure goto3|
+create procedure goto4()
+begin
+begin
+label lab1;
+begin
+goto lab1;
+end;
+end;
+end|
+drop procedure goto4|
+create procedure goto5()
+begin
+begin
+begin
+goto lab1;
+end;
+label lab1;
+end;
+end|
+drop procedure goto5|
+create procedure goto6()
+begin
+label L1;
+goto L5;
+begin
+label L2;
+goto L1;
+goto L5;
+begin
+label L3;
+goto L1;
+goto L2;
+goto L3;
+goto L4;
+goto L5;
+end;
+goto L2;
+goto L4;
+label L4;
+end;
+label L5;
+goto L1;
+end|
+drop procedure goto6|
 insert into t1 values ("foo", 3), ("bar", 19)|
 insert into t2 values ("x", 9, 4.1), ("y", -1, 19.2), ("z", 3, 2.2)|
 create procedure sel1()
@@ -1536,11 +1587,8 @@ show errors;
 show columns from t1;
 show grants for 'root'@'localhost';
 show keys from t1;
-show master status;
 show open tables like 'foo';
 show privileges;
-show slave hosts;
-show slave status;
 show status like 'foo';
 show tables like 'foo';
 show variables like 'foo';
@@ -1567,8 +1615,6 @@ data	int(11)			0
 Grants for root@localhost
 GRANT ALL PRIVILEGES ON *.* TO 'root'@'localhost' WITH GRANT OPTION
 Table	Non_unique	Key_name	Seq_in_index	Column_name	Collation	Cardinality	Sub_part	Packed	Null	Index_type	Comment
-File	Position	Binlog_Do_DB	Binlog_Ignore_DB
-master-bin.000001	22451		
 Database	Table	In_use	Name_locked
 Privilege	Context	Comment
 Alter	Tables	To alter the table
@@ -1594,8 +1640,6 @@ Shutdown	Server Admin	To shut down the server
 Super	Server Admin	To use KILL thread, SET GLOBAL, CHANGE MASTER, etc.
 Update	Tables	To update existing rows
 Usage	Server Admin	No privileges - allow connect only
-Server_id	Host	Port	Rpl_recovery_rank	Master_id
-Slave_IO_State	Master_Host	Master_User	Master_Port	Connect_Retry	Master_Log_File	Read_Master_Log_Pos	Relay_Log_File	Relay_Log_Pos	Relay_Master_Log_File	Slave_IO_Running	Slave_SQL_Running	Replicate_Do_DB	Replicate_Ignore_DB	Replicate_Do_Table	Replicate_Ignore_Table	Replicate_Wild_Do_Table	Replicate_Wild_Ignore_Table	Last_Errno	Last_Error	Skip_Counter	Exec_Master_Log_Pos	Relay_Log_Space	Until_Condition	Until_Log_File	Until_Log_Pos	Master_SSL_Allowed	Master_SSL_CA_File	Master_SSL_CA_Path	Master_SSL_Cert	Master_SSL_Cipher	Master_SSL_Key	Seconds_Behind_Master
 Variable_name	Value
 Tables_in_test (foo)	table_type
 Variable_name	Value
@@ -1621,8 +1665,6 @@ data	int(11)			0
 Grants for root@localhost
 GRANT ALL PRIVILEGES ON *.* TO 'root'@'localhost' WITH GRANT OPTION
 Table	Non_unique	Key_name	Seq_in_index	Column_name	Collation	Cardinality	Sub_part	Packed	Null	Index_type	Comment
-File	Position	Binlog_Do_DB	Binlog_Ignore_DB
-master-bin.000001	22451		
 Database	Table	In_use	Name_locked
 Privilege	Context	Comment
 Alter	Tables	To alter the table
@@ -1648,8 +1690,6 @@ Shutdown	Server Admin	To shut down the server
 Super	Server Admin	To use KILL thread, SET GLOBAL, CHANGE MASTER, etc.
 Update	Tables	To update existing rows
 Usage	Server Admin	No privileges - allow connect only
-Server_id	Host	Port	Rpl_recovery_rank	Master_id
-Slave_IO_State	Master_Host	Master_User	Master_Port	Connect_Retry	Master_Log_File	Read_Master_Log_Pos	Relay_Log_File	Relay_Log_Pos	Relay_Master_Log_File	Slave_IO_Running	Slave_SQL_Running	Replicate_Do_DB	Replicate_Ignore_DB	Replicate_Do_Table	Replicate_Ignore_Table	Replicate_Wild_Do_Table	Replicate_Wild_Ignore_Table	Last_Errno	Last_Error	Skip_Counter	Exec_Master_Log_Pos	Relay_Log_Space	Until_Condition	Until_Log_File	Until_Log_Pos	Master_SSL_Allowed	Master_SSL_CA_File	Master_SSL_CA_Path	Master_SSL_Cert	Master_SSL_Cipher	Master_SSL_Key	Seconds_Behind_Master
 Variable_name	Value
 Tables_in_test (foo)	table_type
 Variable_name	Value

mysql-test/t/sp-error.test

@@ -103,6 +103,42 @@ create procedure foo()
 begin
   goto foo;
 end|
+--error 1307
+create procedure foo()
+begin
+  begin
+    label foo;
+  end;
+  goto foo;
+end|
+--error 1307
+create procedure foo()
+begin
+  goto foo;
+  begin
+    label foo;
+  end;
+end|
+--error 1307
+create procedure foo()
+begin
+  begin
+    goto foo;
+  end;
+  begin
+    label foo;
+  end;
+end|
+--error 1307
+create procedure foo()
+begin
+  begin
+    label foo;
+  end;
+  begin
+    goto foo;
+  end;
+end|
 
 # Redefining label
 --error 1308
@@ -380,6 +416,18 @@ begin
   declare c cursor for select * from t1;
 end|
 
+--error 1357
+create procedure p()
+begin
+  declare continue handler for sqlexception
+    begin
+      goto L1;
+    end;
+
+  select field from t1;
+  label L1;
+end|
+
 #
 # BUG#1965
 #

mysql-test/t/sp.test

 #
 # Basic stored PROCEDURE tests
 #
-#
-
-# Let us reset binary logs in order to make show master status 
-# in test for bug 4902 repeatable.
-reset master;
+# Please keep this file free of --error cases and other
+# things that will not run in a single debugged mysqld
+# process (e.g. master-slave things).
 
 use test;
 
@@ -470,10 +468,10 @@ drop procedure i|
 
 # The non-standard GOTO, for compatibility
 #
-# QQQ The "label" syntax is temporary.
-# QQQ This is no nearly enough, more tests are needed
+# QQQ The "label" syntax is temporary, it will (hopefully)
+#     change to the more common "L:" syntax soon.
 #
-create procedure j()
+create procedure goto1()
 begin
   declare y int;
 
@@ -488,12 +486,11 @@ label a;
 label b;
 end|
 
-call j()|
-
-drop procedure j|
+call goto1()|
+drop procedure goto1|
 
 # With dummy handlers, just to test restore of contexts with jumps
-create procedure k(a int)
+create procedure goto2(a int)
 begin
   declare x int default 0;
   declare continue handler for sqlstate '42S98' set x = 1;
@@ -520,13 +517,70 @@ b:
   select * from t1;
 end|
 
-call k(0)|
-call k(1)|
-call k(2)|
+call goto2(0)|
+call goto2(1)|
+call goto2(2)|
 
-drop procedure k|
+drop procedure goto2|
 delete from t1|
 
+# Check label visibility for some more cases. We don't call these.
+create procedure goto3()
+begin
+ label L1;
+   begin
+   end;
+ goto L1;
+end|
+drop procedure goto3|
+
+create procedure goto4()
+begin
+  begin
+   label lab1;
+    begin
+      goto lab1;
+    end;
+  end;
+end|
+drop procedure goto4|
+
+create procedure goto5()
+begin
+  begin
+    begin
+      goto lab1;
+    end;
+   label lab1;
+  end;
+end|
+drop procedure goto5|
+
+create procedure goto6()
+begin
+  label L1;
+  goto L5;
+  begin
+    label L2;
+    goto L1;
+    goto L5;
+    begin
+      label L3;
+      goto L1;
+      goto L2;
+      goto L3;
+      goto L4;
+      goto L5;
+    end;
+    goto L2;
+    goto L4;
+    label L4;
+  end;
+  label L5;
+  goto L1;
+end|
+drop procedure goto6|
+
 # SELECT with one of more result set sent back to the clinet
 insert into t1 values ("foo", 3), ("bar", 19)|
 insert into t2 values ("x", 9, 4.1), ("y", -1, 19.2), ("z", 3, 2.2)|
@@ -1761,11 +1815,8 @@ begin
   show columns from t1;
   show grants for 'root'@'localhost';
   show keys from t1;
-  show master status;
   show open tables like 'foo';
   show privileges;
-  show slave hosts;
-  show slave status;
   show status like 'foo';
   show tables like 'foo';
   show variables like 'foo';
@@ -1773,6 +1824,9 @@ begin
 end|
 #show binlog events;
 #show storage engines;
+#show master status;
+#show slave hosts;
+#show slave status;
 
 call bug4902()|
 call bug4902()|

sql/share/czech/errmsg.txt

@@ -369,3 +369,4 @@ character-set=latin2
 "View being updated does not have complete key of underlying table in it"
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"

sql/share/danish/errmsg.txt

@@ -363,3 +363,4 @@ character-set=latin1
 "View being updated does not have complete key of underlying table in it"
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"

sql/share/dutch/errmsg.txt

@@ -371,3 +371,4 @@ character-set=latin1
 "View being updated does not have complete key of underlying table in it"
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"

sql/share/english/errmsg.txt

@@ -360,3 +360,4 @@ character-set=latin1
 "View being updated does not have complete key of underlying table in it"
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"

sql/share/estonian/errmsg.txt

@@ -365,3 +365,4 @@ character-set=latin7
 "View being updated does not have complete key of underlying table in it"
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"

sql/share/french/errmsg.txt

@@ -360,3 +360,4 @@ character-set=latin1
 "View being updated does not have complete key of underlying table in it"
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"

sql/share/german/errmsg.txt

@@ -372,3 +372,4 @@ character-set=latin1
 "View being updated does not have complete key of underlying table in it"
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"

sql/share/greek/errmsg.txt

@@ -360,3 +360,4 @@ character-set=greek
 "View being updated does not have complete key of underlying table in it"
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"

sql/share/hungarian/errmsg.txt

@@ -362,3 +362,4 @@ character-set=latin2
 "View being updated does not have complete key of underlying table in it"
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"

sql/share/italian/errmsg.txt

@@ -360,3 +360,4 @@ character-set=latin1
 "View being updated does not have complete key of underlying table in it"
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"

sql/share/japanese/errmsg.txt

@@ -362,3 +362,4 @@ character-set=ujis
 "View being updated does not have complete key of underlying table in it"
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"

sql/share/korean/errmsg.txt

@@ -360,3 +360,4 @@ character-set=euckr
 "View being updated does not have complete key of underlying table in it"
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"

sql/share/norwegian-ny/errmsg.txt

@@ -362,3 +362,4 @@ character-set=latin1
 "View being updated does not have complete key of underlying table in it"
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"

sql/share/norwegian/errmsg.txt

@@ -362,3 +362,4 @@ character-set=latin1
 "View being updated does not have complete key of underlying table in it"
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"

sql/share/polish/errmsg.txt

@@ -364,3 +364,4 @@ character-set=latin2
 "View being updated does not have complete key of underlying table in it"
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"

sql/share/portuguese/errmsg.txt

@@ -361,3 +361,4 @@ character-set=latin1
 "View being updated does not have complete key of underlying table in it"
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"

sql/share/romanian/errmsg.txt

@@ -364,3 +364,4 @@ character-set=latin2
 "View being updated does not have complete key of underlying table in it"
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"

sql/share/russian/errmsg.txt

@@ -362,3 +362,4 @@ character-set=koi8r
 " view       ()"
 "View '%-.64s.%-.64s'      "
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"

sql/share/serbian/errmsg.txt

@@ -366,3 +366,4 @@ character-set=cp1250
 "View being updated does not have complete key of underlying table in it"
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"

sql/share/slovak/errmsg.txt

@@ -368,3 +368,4 @@ character-set=latin2
 "View being updated does not have complete key of underlying table in it"
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"

sql/share/spanish/errmsg.txt

@@ -362,3 +362,4 @@ character-set=latin1
 "View being updated does not have complete key of underlying table in it"
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"

sql/share/swedish/errmsg.txt

@@ -360,3 +360,4 @@ character-set=latin1
 "View being updated does not have complete key of underlying table in it"
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"

sql/share/ukrainian/errmsg.txt

@@ -365,3 +365,4 @@ character-set=koi8u
 "View,  ,  ͦ   æ(),  Ҧ  "
 "View '%-.64s.%-.64s'   Ŧަ æ  æ"
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"

sql/sp_head.cc

@@ -257,7 +257,7 @@ sp_head::operator delete(void *ptr, size_t size)
 
 sp_head::sp_head()
   :Item_arena((bool)FALSE), m_returns_cs(NULL), m_has_return(FALSE),
-   m_simple_case(FALSE), m_multi_results(FALSE)
+   m_simple_case(FALSE), m_multi_results(FALSE), m_in_handler(FALSE)
 {
   DBUG_ENTER("sp_head::sp_head");
 
@@ -272,7 +272,7 @@ sp_head::init(LEX *lex)
 {
   DBUG_ENTER("sp_head::init");
 
-  lex->spcont= m_pcont= new sp_pcontext();
+  lex->spcont= m_pcont= new sp_pcontext(NULL);
   my_init_dynamic_array(&m_instr, sizeof(sp_instr *), 16, 8);
   m_param_begin= m_param_end= m_returns_begin= m_returns_end= m_body_begin= 0;
   m_qname.str= m_db.str= m_name.str= m_params.str= m_retstr.str=
@@ -514,10 +514,10 @@ sp_head::execute_function(THD *thd, Item **argp, uint argcount, Item **resp)
 {
   DBUG_ENTER("sp_head::execute_function");
   DBUG_PRINT("info", ("function %s", m_name.str));
-  uint csize = m_pcont->max_framesize();
-  uint params = m_pcont->params();
-  uint hmax = m_pcont->handlers();
-  uint cmax = m_pcont->cursors();
+  uint csize = m_pcont->max_pvars();
+  uint params = m_pcont->current_pvars();
+  uint hmax = m_pcont->max_handlers();
+  uint cmax = m_pcont->max_cursors();
   sp_rcontext *octx = thd->spcont;
   sp_rcontext *nctx = NULL;
   uint i;
@@ -594,10 +594,10 @@ sp_head::execute_procedure(THD *thd, List<Item> *args)
   DBUG_ENTER("sp_head::execute_procedure");
   DBUG_PRINT("info", ("procedure %s", m_name.str));
   int ret= 0;
-  uint csize = m_pcont->max_framesize();
-  uint params = m_pcont->params();
-  uint hmax = m_pcont->handlers();
-  uint cmax = m_pcont->cursors();
+  uint csize = m_pcont->max_pvars();
+  uint params = m_pcont->current_pvars();
+  uint hmax = m_pcont->max_handlers();
+  uint cmax = m_pcont->max_cursors();
   sp_rcontext *octx = thd->spcont;
   sp_rcontext *nctx = NULL;
   my_bool tmp_octx = FALSE;	// True if we have allocated a temporary octx
@@ -851,12 +851,18 @@ sp_head::backpatch(sp_label_t *lab)
 	(bp->lab->type == SP_LAB_REF &&
 	 my_strcasecmp(system_charset_info, bp->lab->name, lab->name) == 0))
     {
-      sp_scope_t sdiff;
+      if (bp->lab->type != SP_LAB_REF)
+	bp->instr->backpatch(dest, lab->ctx);
+      else
+      {
+	sp_label_t *dstlab= bp->lab->ctx->find_label(lab->name);
 
-      if (bp->lab->type == SP_LAB_REF)
+	if (dstlab)
+	{
 	  bp->lab= lab;
-      m_pcont->diff_scopes(0, &sdiff);
-      bp->instr->backpatch(dest, sdiff.hndlrs, sdiff.curs);
+	  bp->instr->backpatch(dest, dstlab->ctx);
+	}
+      }
     }
   }
 }
@@ -1236,7 +1242,7 @@ sp_instr_jump::print(String *str)
 uint
 sp_instr_jump::opt_mark(sp_head *sp)
 {
-  m_dest= opt_shortcut_jump(sp);
+  m_dest= opt_shortcut_jump(sp, this);
   if (m_dest != m_ip+1)		/* Jumping to following instruction? */
     marked= 1;
   m_optdest= sp->get_instr(m_dest);
@@ -1244,15 +1250,18 @@ sp_instr_jump::opt_mark(sp_head *sp)
 }
 
 uint
-sp_instr_jump::opt_shortcut_jump(sp_head *sp)
+sp_instr_jump::opt_shortcut_jump(sp_head *sp, sp_instr *start)
 {
   uint dest= m_dest;
   sp_instr *i;
 
   while ((i= sp->get_instr(dest)))
   {
-    uint ndest= i->opt_shortcut_jump(sp);
+    uint ndest;
 
+    if (start == i)
+      break;
+    ndest= i->opt_shortcut_jump(sp, start);
     if (ndest == dest)
       break;
     dest= ndest;
@@ -1320,7 +1329,7 @@ sp_instr_jump_if::opt_mark(sp_head *sp)
   marked= 1;
   if ((i= sp->get_instr(m_dest)))
   {
-    m_dest= i->opt_shortcut_jump(sp);
+    m_dest= i->opt_shortcut_jump(sp, this);
     m_optdest= sp->get_instr(m_dest);
   }
   sp->opt_mark(m_dest);
@@ -1377,7 +1386,7 @@ sp_instr_jump_if_not::opt_mark(sp_head *sp)
   marked= 1;
   if ((i= sp->get_instr(m_dest)))
   {
-    m_dest= i->opt_shortcut_jump(sp);
+    m_dest= i->opt_shortcut_jump(sp, this);
     m_optdest= sp->get_instr(m_dest);
   }
   sp->opt_mark(m_dest);
@@ -1460,7 +1469,7 @@ sp_instr_hpush_jump::opt_mark(sp_head *sp)
   marked= 1;
   if ((i= sp->get_instr(m_dest)))
   {
-    m_dest= i->opt_shortcut_jump(sp);
+    m_dest= i->opt_shortcut_jump(sp, this);
     m_optdest= sp->get_instr(m_dest);
   }
   sp->opt_mark(m_dest);
@@ -1487,6 +1496,13 @@ sp_instr_hpop::print(String *str)
   str->qs_append(m_count);
 }
 
+void
+sp_instr_hpop::backpatch(uint dest, sp_pcontext *dst_ctx)
+{
+  m_count= m_ctx->diff_handlers(dst_ctx);
+}
+
+
 //
 // sp_instr_hreturn
 //
@@ -1551,6 +1567,12 @@ sp_instr_cpop::print(String *str)
   str->qs_append(m_count);
 }
 
+void
+sp_instr_cpop::backpatch(uint dest, sp_pcontext *dst_ctx)
+{
+  m_count= m_ctx->diff_cursors(dst_ctx);
+}
+
 //
 // sp_instr_copen
 //

sql/sp_head.h

@@ -86,6 +86,7 @@ class sp_head :private Item_arena
   my_bool m_has_return;		// For FUNCTIONs only
   my_bool m_simple_case;	// TRUE if parsing simple case, FALSE otherwise
   my_bool m_multi_results;	// TRUE if a procedure with SELECT(s)
+  my_bool m_in_handler;		// TRUE if parser in a handler body
   uint m_old_cmq;		// Old CLIENT_MULTI_QUERIES value
   st_sp_chistics *m_chistics;
   ulong m_sql_mode;		// For SHOW CREATE
@@ -262,10 +263,11 @@ class sp_instr : public Sql_alloc
   uint marked;
   Item *free_list;              // My Items
   uint m_ip;			// My index
+  sp_pcontext *m_ctx;		// My parse context
 
   // Should give each a name or type code for debugging purposes?
-  sp_instr(uint ip)
-    :Sql_alloc(), marked(0), free_list(0), m_ip(ip)
+  sp_instr(uint ip, sp_pcontext *ctx)
+    :Sql_alloc(), marked(0), free_list(0), m_ip(ip), m_ctx(ctx)
   {}
 
   virtual ~sp_instr()
@@ -279,7 +281,7 @@ class sp_instr : public Sql_alloc
 
   virtual void print(String *str) = 0;
 
-  virtual void backpatch(uint dest, uint hpop, uint cpop)
+  virtual void backpatch(uint dest, sp_pcontext *dst_ctx)
   {}
 
   virtual uint opt_mark(sp_head *sp)
@@ -288,7 +290,7 @@ class sp_instr : public Sql_alloc
     return m_ip+1;
   }
 
-  virtual uint opt_shortcut_jump(sp_head *sp)
+  virtual uint opt_shortcut_jump(sp_head *sp, sp_instr *start)
   {
     return m_ip;
   }
@@ -311,8 +313,8 @@ class sp_instr_stmt : public sp_instr
 
 public:
 
-  sp_instr_stmt(uint ip)
-    : sp_instr(ip), m_lex(NULL)
+  sp_instr_stmt(uint ip, sp_pcontext *ctx)
+    : sp_instr(ip, ctx), m_lex(NULL)
   {}
 
   virtual ~sp_instr_stmt();
@@ -353,8 +355,10 @@ class sp_instr_set : public sp_instr
 
   TABLE_LIST *tables;
 
-  sp_instr_set(uint ip, uint offset, Item *val, enum enum_field_types type)
-    : sp_instr(ip), tables(NULL), m_offset(offset), m_value(val), m_type(type)
+  sp_instr_set(uint ip, sp_pcontext *ctx,
+	       uint offset, Item *val, enum enum_field_types type)
+    : sp_instr(ip, ctx),
+      tables(NULL), m_offset(offset), m_value(val), m_type(type)
   {}
 
   virtual ~sp_instr_set()
@@ -382,12 +386,12 @@ class sp_instr_jump : public sp_instr
 
   uint m_dest;			// Where we will go
 
-  sp_instr_jump(uint ip)
-    : sp_instr(ip), m_dest(0), m_optdest(0)
+  sp_instr_jump(uint ip, sp_pcontext *ctx)
+    : sp_instr(ip, ctx), m_dest(0), m_optdest(0)
   {}
 
-  sp_instr_jump(uint ip, uint dest)
-    : sp_instr(ip), m_dest(dest), m_optdest(0)
+  sp_instr_jump(uint ip, sp_pcontext *ctx, uint dest)
+    : sp_instr(ip, ctx), m_dest(dest), m_optdest(0)
   {}
 
   virtual ~sp_instr_jump()
@@ -399,11 +403,11 @@ class sp_instr_jump : public sp_instr
 
   virtual uint opt_mark(sp_head *sp);
 
-  virtual uint opt_shortcut_jump(sp_head *sp);
+  virtual uint opt_shortcut_jump(sp_head *sp, sp_instr *start);
 
   virtual void opt_move(uint dst, List<sp_instr> *ibp);
 
-  virtual void backpatch(uint dest, uint hpop, uint cpop)
+  virtual void backpatch(uint dest, sp_pcontext *dst_ctx)
   {
     if (m_dest == 0)		// Don't reset
       m_dest= dest;
@@ -425,12 +429,12 @@ class sp_instr_jump_if : public sp_instr_jump
 
   TABLE_LIST *tables;
 
-  sp_instr_jump_if(uint ip, Item *i)
-    : sp_instr_jump(ip), tables(NULL), m_expr(i)
+  sp_instr_jump_if(uint ip, sp_pcontext *ctx, Item *i)
+    : sp_instr_jump(ip, ctx), tables(NULL), m_expr(i)
   {}
 
-  sp_instr_jump_if(uint ip, Item *i, uint dest)
-    : sp_instr_jump(ip, dest), tables(NULL), m_expr(i)
+  sp_instr_jump_if(uint ip, sp_pcontext *ctx, Item *i, uint dest)
+    : sp_instr_jump(ip, ctx, dest), tables(NULL), m_expr(i)
   {}
 
   virtual ~sp_instr_jump_if()
@@ -442,7 +446,7 @@ class sp_instr_jump_if : public sp_instr_jump
 
   virtual uint opt_mark(sp_head *sp);
 
-  virtual uint opt_shortcut_jump(sp_head *sp)
+  virtual uint opt_shortcut_jump(sp_head *sp, sp_instr *start)
   {
     return m_ip;
   }
@@ -463,12 +467,12 @@ class sp_instr_jump_if_not : public sp_instr_jump
 
   TABLE_LIST *tables;
 
-  sp_instr_jump_if_not(uint ip, Item *i)
-    : sp_instr_jump(ip), tables(NULL), m_expr(i)
+  sp_instr_jump_if_not(uint ip, sp_pcontext *ctx, Item *i)
+    : sp_instr_jump(ip, ctx), tables(NULL), m_expr(i)
   {}
 
-  sp_instr_jump_if_not(uint ip, Item *i, uint dest)
-    : sp_instr_jump(ip, dest), tables(NULL), m_expr(i)
+  sp_instr_jump_if_not(uint ip, sp_pcontext *ctx, Item *i, uint dest)
+    : sp_instr_jump(ip, ctx, dest), tables(NULL), m_expr(i)
   {}
 
   virtual ~sp_instr_jump_if_not()
@@ -480,7 +484,7 @@ class sp_instr_jump_if_not : public sp_instr_jump
 
   virtual uint opt_mark(sp_head *sp);
 
-  virtual uint opt_shortcut_jump(sp_head *sp)
+  virtual uint opt_shortcut_jump(sp_head *sp, sp_instr *start)
   {
     return m_ip;
   }
@@ -501,8 +505,9 @@ class sp_instr_freturn : public sp_instr
 
   TABLE_LIST *tables;
 
-  sp_instr_freturn(uint ip, Item *val, enum enum_field_types type)
-    : sp_instr(ip), tables(NULL), m_value(val), m_type(type)
+  sp_instr_freturn(uint ip, sp_pcontext *ctx,
+		   Item *val, enum enum_field_types type)
+    : sp_instr(ip, ctx), tables(NULL), m_value(val), m_type(type)
   {}
 
   virtual ~sp_instr_freturn()
@@ -533,8 +538,8 @@ class sp_instr_hpush_jump : public sp_instr_jump
 
 public:
 
-  sp_instr_hpush_jump(uint ip, int htype, uint fp)
-    : sp_instr_jump(ip), m_type(htype), m_frame(fp)
+  sp_instr_hpush_jump(uint ip, sp_pcontext *ctx, int htype, uint fp)
+    : sp_instr_jump(ip, ctx), m_type(htype), m_frame(fp)
   {
     m_handler= ip+1;
     m_cond.empty();
@@ -551,7 +556,7 @@ class sp_instr_hpush_jump : public sp_instr_jump
 
   virtual uint opt_mark(sp_head *sp);
 
-  virtual uint opt_shortcut_jump(sp_head *sp)
+  virtual uint opt_shortcut_jump(sp_head *sp, sp_instr *start)
   {
     return m_ip;
   }
@@ -578,8 +583,8 @@ class sp_instr_hpop : public sp_instr
 
 public:
 
-  sp_instr_hpop(uint ip, uint count)
-    : sp_instr(ip), m_count(count)
+  sp_instr_hpop(uint ip, sp_pcontext *ctx, uint count)
+    : sp_instr(ip, ctx), m_count(count)
   {}
 
   virtual ~sp_instr_hpop()
@@ -589,13 +594,7 @@ class sp_instr_hpop : public sp_instr
 
   virtual void print(String *str);
 
-  virtual void backpatch(uint dest, uint hpop, uint cpop)
-  {
-    if (hpop > m_count)
-      m_count= 0;
-    else
-      m_count-= hpop;
-  }
+  virtual void backpatch(uint dest, sp_pcontext *dst_ctx);
 
   virtual uint opt_mark(sp_head *sp)
   {
@@ -618,8 +617,8 @@ class sp_instr_hreturn : public sp_instr
 
 public:
 
-  sp_instr_hreturn(uint ip, uint fp)
-    : sp_instr(ip), m_frame(fp)
+  sp_instr_hreturn(uint ip, sp_pcontext *ctx, uint fp)
+    : sp_instr(ip, ctx), m_frame(fp)
   {}
 
   virtual ~sp_instr_hreturn()
@@ -649,8 +648,8 @@ class sp_instr_cpush : public sp_instr
 
 public:
 
-  sp_instr_cpush(uint ip, LEX *lex)
-    : sp_instr(ip), m_lex(lex)
+  sp_instr_cpush(uint ip, sp_pcontext *ctx, LEX *lex)
+    : sp_instr(ip, ctx), m_lex(lex)
   {}
 
   virtual ~sp_instr_cpush();
@@ -673,8 +672,8 @@ class sp_instr_cpop : public sp_instr
 
 public:
 
-  sp_instr_cpop(uint ip, uint count)
-    : sp_instr(ip), m_count(count)
+  sp_instr_cpop(uint ip, sp_pcontext *ctx, uint count)
+    : sp_instr(ip, ctx), m_count(count)
   {}
 
   virtual ~sp_instr_cpop()
@@ -684,13 +683,7 @@ class sp_instr_cpop : public sp_instr
 
   virtual void print(String *str);
 
-  virtual void backpatch(uint dest, uint hpop, uint cpop)
-  {
-    if (cpop > m_count)
-      m_count= 0;
-    else
-      m_count-= cpop;
-  }
+  virtual void backpatch(uint dest, sp_pcontext *dst_ctx);
 
   virtual uint opt_mark(sp_head *sp)
   {
@@ -713,8 +706,8 @@ class sp_instr_copen : public sp_instr_stmt
 
 public:
 
-  sp_instr_copen(uint ip, uint c)
-    : sp_instr_stmt(ip), m_cursor(c)
+  sp_instr_copen(uint ip, sp_pcontext *ctx, uint c)
+    : sp_instr_stmt(ip, ctx), m_cursor(c)
   {}
 
   virtual ~sp_instr_copen()
@@ -738,8 +731,8 @@ class sp_instr_cclose : public sp_instr
 
 public:
 
-  sp_instr_cclose(uint ip, uint c)
-    : sp_instr(ip), m_cursor(c)
+  sp_instr_cclose(uint ip, sp_pcontext *ctx, uint c)
+    : sp_instr(ip, ctx), m_cursor(c)
   {}
 
   virtual ~sp_instr_cclose()
@@ -763,8 +756,8 @@ class sp_instr_cfetch : public sp_instr
 
 public:
 
-  sp_instr_cfetch(uint ip, uint c)
-    : sp_instr(ip), m_cursor(c)
+  sp_instr_cfetch(uint ip, sp_pcontext *ctx, uint c)
+    : sp_instr(ip, ctx), m_cursor(c)
   {
     m_varlist.empty();
   }
@@ -796,8 +789,8 @@ class sp_instr_error : public sp_instr
 
 public:
 
-  sp_instr_error(uint ip, int errcode)
-    : sp_instr(ip), m_errcode(errcode)
+  sp_instr_error(uint ip, sp_pcontext *ctx, int errcode)
+    : sp_instr(ip, ctx), m_errcode(errcode)
   {}
 
   virtual ~sp_instr_error()

sql/sp_pcontext.cc

@@ -26,79 +26,98 @@
 #include "sp_pcontext.h"
 #include "sp_head.h"
 
-sp_pcontext::sp_pcontext()
-  : Sql_alloc(), m_params(0), m_framesize(0), m_handlers(0), m_cursmax(0),
-    m_hndlrlev(0)
+sp_pcontext::sp_pcontext(sp_pcontext *prev)
+  : Sql_alloc(), m_psubsize(0), m_csubsize(0), m_hsubsize(0),
+    m_parent(prev), m_handlers(0)
 {
   VOID(my_init_dynamic_array(&m_pvar, sizeof(sp_pvar_t *), 16, 8));
   VOID(my_init_dynamic_array(&m_cond, sizeof(sp_cond_type_t *), 16, 8));
   VOID(my_init_dynamic_array(&m_cursor, sizeof(LEX_STRING), 16, 8));
-  VOID(my_init_dynamic_array(&m_scopes, sizeof(sp_scope_t), 16, 8));
-  VOID(my_init_dynamic_array(&m_glabel, sizeof(sp_label_t *), 16, 8));
   m_label.empty();
+  m_children.empty();
+  if (!prev)
+    m_poffset= m_coffset= 0;
+  else
+  {
+    m_poffset= prev->current_pvars();
+    m_coffset= prev->current_cursors();
+  }
 }
 
 void
 sp_pcontext::destroy()
 {
+  List_iterator_fast<sp_pcontext> li(m_children);
+  sp_pcontext *child;
+
+  while ((child= li++))
+    child->destroy();
+
+  m_children.empty();
+  m_label.empty();
   delete_dynamic(&m_pvar);
   delete_dynamic(&m_cond);
   delete_dynamic(&m_cursor);
-  delete_dynamic(&m_scopes);
-  delete_dynamic(&m_glabel);
-  m_label.empty();
 }
 
-void
-sp_pcontext::push_scope()
+sp_pcontext *
+sp_pcontext::push_context()
 {
-  sp_scope_t s;
-
-  s.vars= m_pvar.elements;
-  s.conds= m_cond.elements;
-  s.hndlrs= m_hndlrlev;
-  s.curs= m_cursor.elements;
-  s.glab= m_glabel.elements;
-  insert_dynamic(&m_scopes, (gptr)&s);
+  sp_pcontext *child= new sp_pcontext(this);
+
+  if (child)
+    m_children.push_back(child);
+  return child;
 }
 
-void
-sp_pcontext::pop_scope(sp_scope_t *sp)
+sp_pcontext *
+sp_pcontext::pop_context()
 {
-  byte *p= pop_dynamic(&m_scopes);
-
-  if (sp && p)
-    memcpy(sp, p, sizeof(sp_scope_t));
+  uint submax= max_pvars();
+
+  if (submax > m_parent->m_psubsize)
+    m_parent->m_psubsize= submax;
+  submax= max_handlers();
+  if (submax > m_parent->m_hsubsize)
+    m_parent->m_hsubsize= submax;
+  submax= max_cursors();
+  if (submax > m_parent->m_csubsize)
+    m_parent->m_csubsize= submax;
+  return m_parent;
 }
 
-void
-sp_pcontext::diff_scopes(uint sold, sp_scope_t *diffs)
+uint
+sp_pcontext::diff_handlers(sp_pcontext *ctx)
 {
-  uint snew= m_scopes.elements;
-  sp_scope_t scope;
+  uint n= 0;
+  sp_pcontext *pctx= this;
 
-  diffs->vars= diffs->conds= diffs->hndlrs= diffs->curs= diffs->glab= 0;
-  while (snew-- > sold)
+  while (pctx && pctx != ctx)
   {
-    get_dynamic(&m_scopes, (gptr)&scope, snew);
-    diffs->vars+= scope.vars;
-    diffs->conds+= scope.conds;
-    diffs->hndlrs+= scope.hndlrs;
-    diffs->curs+= scope.curs;
-    diffs->glab+= scope.glab;
+    n+= pctx->max_handlers();
+    pctx= pctx->parent_context();
   }
-  if (sold)
+  if (pctx)
+    return n;
+  return 0;			// Didn't find ctx
+}
+
+uint
+sp_pcontext::diff_cursors(sp_pcontext *ctx)
+{
+  uint n= 0;
+  sp_pcontext *pctx= this;
+
+  while (pctx && pctx != ctx)
   {
-    get_dynamic(&m_scopes, (gptr)&scope, sold-1);
-    diffs->vars-= scope.vars;
-    diffs->conds-= scope.conds;
-    diffs->hndlrs-= scope.hndlrs;
-    diffs->curs-= scope.curs;
-    diffs->glab-= scope.glab;
+    n+= pctx->max_cursors();
+    pctx= pctx->parent_context();
   }
+  if (pctx)
+    return n;
+  return 0;			// Didn't find ctx
 }
 
-
 /* This does a linear search (from newer to older variables, in case
 ** we have shadowed names).
 ** It's possible to have a more efficient allocation and search method,
@@ -109,20 +128,9 @@ sp_pcontext::diff_scopes(uint sold, sp_scope_t *diffs)
 sp_pvar_t *
 sp_pcontext::find_pvar(LEX_STRING *name, my_bool scoped)
 {
-  uint i = m_pvar.elements;
-  uint limit;
+  uint i= m_pvar.elements;
 
-  if (! scoped || m_scopes.elements == 0)
-    limit= 0;
-  else
-  {
-    sp_scope_t s;
-
-    get_dynamic(&m_scopes, (gptr)&s, m_scopes.elements-1);
-    limit= s.vars;
-  }
-      
-  while (i-- > limit)
+  while (i--)
   {
     sp_pvar_t *p;
 
@@ -134,6 +142,8 @@ sp_pcontext::find_pvar(LEX_STRING *name, my_bool scoped)
       return p;
     }
   }
+  if (!scoped && m_parent)
+    return m_parent->find_pvar(name, scoped);
   return NULL;
 }
 
@@ -145,13 +155,13 @@ sp_pcontext::push_pvar(LEX_STRING *name, enum enum_field_types type,
 
   if (p)
   {
-    if (m_pvar.elements == m_framesize)
-      m_framesize += 1;
+    if (m_pvar.elements == m_psubsize)
+      m_psubsize+= 1;
     p->name.str= name->str;
     p->name.length= name->length;
     p->type= type;
     p->mode= mode;
-    p->offset= m_pvar.elements;
+    p->offset= current_pvars();
     p->isset= (mode == sp_param_out ? FALSE : TRUE);
     p->dflt= NULL;
     insert_dynamic(&m_pvar, (gptr)&p);
@@ -168,7 +178,7 @@ sp_pcontext::push_label(char *name, uint ip)
     lab->name= name;
     lab->ip= ip;
     lab->type= SP_LAB_GOTO;
-    lab->scopes= 0;
+    lab->ctx= this;
     m_label.push_front(lab);
   }
   return lab;
@@ -184,6 +194,8 @@ sp_pcontext::find_label(char *name)
     if (my_strcasecmp(system_charset_info, name, lab->name) == 0)
       return lab;
 
+  if (m_parent)
+    return m_parent->find_label(name);
   return NULL;
 }
 
@@ -207,20 +219,9 @@ sp_pcontext::push_cond(LEX_STRING *name, sp_cond_type_t *val)
 sp_cond_type_t *
 sp_pcontext::find_cond(LEX_STRING *name, my_bool scoped)
 {
-  uint i = m_cond.elements;
-  uint limit;
-
-  if (! scoped || m_scopes.elements == 0)
-    limit= 0;
-  else
-  {
-    sp_scope_t s;
-
-    get_dynamic(&m_scopes, (gptr)&s, m_scopes.elements-1);
-    limit= s.conds;
-  }
+  uint i= m_cond.elements;
 
-  while (i-- > limit)
+  while (i--)
   {
     sp_cond_t *p;
 
@@ -232,6 +233,8 @@ sp_pcontext::find_cond(LEX_STRING *name, my_bool scoped)
       return p->val;
     }
   }
+  if (!scoped && m_parent)
+    return m_parent->find_cond(name, scoped);
   return NULL;
 }
 
@@ -240,11 +243,11 @@ sp_pcontext::push_cursor(LEX_STRING *name)
 {
   LEX_STRING n;
 
+  if (m_cursor.elements == m_csubsize)
+    m_csubsize+= 1;
   n.str= name->str;
   n.length= name->length;
   insert_dynamic(&m_cursor, (gptr)&n);
-  if (m_cursor.elements > m_cursmax)
-    m_cursmax= m_cursor.elements;
 }
 
 /*
@@ -253,20 +256,9 @@ sp_pcontext::push_cursor(LEX_STRING *name)
 my_bool
 sp_pcontext::find_cursor(LEX_STRING *name, uint *poff, my_bool scoped)
 {
-  uint i = m_cursor.elements;
-  uint limit;
+  uint i= m_cursor.elements;
 
-  if (! scoped || m_scopes.elements == 0)
-    limit= 0;
-  else
-  {
-    sp_scope_t s;
-
-    get_dynamic(&m_scopes, (gptr)&s, m_scopes.elements-1);
-    limit= s.curs;
-  }
-      
-  while (i-- > limit)
+  while (i--)
   {
     LEX_STRING n;
 
@@ -279,43 +271,7 @@ sp_pcontext::find_cursor(LEX_STRING *name, uint *poff, my_bool scoped)
       return TRUE;
     }
   }
+  if (!scoped && m_parent)
+    return m_parent->find_cursor(name, poff, scoped);
   return FALSE;
 }
-
-sp_label_t *
-sp_pcontext::push_glabel(char *name, uint ip)
-{
-  sp_label_t *lab = (sp_label_t *)sql_alloc(sizeof(sp_label_t));
-
-  if (lab)
-  {
-    lab->name= name;
-    lab->ip= ip;
-    lab->type= SP_LAB_GOTO;
-    lab->scopes= 0;
-    insert_dynamic(&m_glabel, (gptr)&lab);
-  }
-  return lab;
-}
-
-sp_label_t *
-sp_pcontext::find_glabel(char *name)
-{
-  uint i= m_glabel.elements;
-
-  while (i--)
-  {
-    sp_label_t *lab;
-
-    get_dynamic(&m_glabel, (gptr)&lab, i);
-    if (my_strcasecmp(system_charset_info, name, lab->name) == 0)
-      return lab;
-  }
-  return NULL;
-}
-
-void
-sp_pcontext::pop_glabel(uint count)
-{
-  (void)pop_dynamic(&m_glabel);  
-}

sql/sp_pcontext.h

@@ -50,7 +50,7 @@ typedef struct sp_label
   char *name;
   uint ip;			// Instruction index
   int type;			// begin/iter or ref/free 
-  uint scopes;			// No. of scopes at label
+  struct sp_pcontext *ctx;	// The label's context
 } sp_label_t;
 
 typedef struct sp_cond_type
@@ -66,11 +66,6 @@ typedef struct sp_cond
   sp_cond_type_t *val;
 } sp_cond_t;
 
-typedef struct sp_scope
-{
-  uint vars, conds, hndlrs, curs, glab;
-} sp_scope_t;
-
 class sp_pcontext : public Sql_alloc
 {
   sp_pcontext(const sp_pcontext &); /* Prevent use of these */
@@ -78,28 +73,30 @@ class sp_pcontext : public Sql_alloc
 
  public:
 
-  sp_pcontext();
+  sp_pcontext(sp_pcontext *prev);
 
   // Free memory
   void
   destroy();
 
-  // For error checking of duplicate things
-  void
-  push_scope();
+  sp_pcontext *
+  push_context();
 
-  void
-  pop_scope(sp_scope_t *sp = 0);
+  // Returns the previous context, not the one we pop
+  sp_pcontext *
+  pop_context();
 
-  uint
-  scopes()
+  sp_pcontext *
+  parent_context()
   {
-    return m_scopes.elements;
+    return m_parent;
   }
 
-  // Sets '*diffs' to the differences between current scope index snew and sold
-  void
-  diff_scopes(uint sold, sp_scope_t *diffs);
+  uint
+  diff_handlers(sp_pcontext *ctx);
+
+  uint
+  diff_cursors(sp_pcontext *ctx);
 
 
   //
@@ -107,28 +104,27 @@ class sp_pcontext : public Sql_alloc
   //
 
   inline uint
-  max_framesize()
+  max_pvars()
   {
-    return m_framesize;
+    return m_psubsize + m_pvar.elements;
   }
 
   inline uint
-  current_framesize()
+  current_pvars()
   {
-    return m_pvar.elements;
+    return m_poffset + m_pvar.elements;
   }
 
   inline uint
-  params()
+  context_pvars()
   {
-    return m_params;
+    return m_pvar.elements;
   }
 
-  // Set the number of parameters to the current esize
-  inline void
-  set_params()
+  inline uint
+  pvar_context2index(uint i)
   {
-    m_params= m_pvar.elements;
+    return m_poffset + i;
   }
 
   inline void
@@ -199,7 +195,11 @@ class sp_pcontext : public Sql_alloc
   inline sp_label_t *
   last_label()
   {
-    return m_label.head();
+    sp_label_t *lab= m_label.head();
+
+    if (!lab && m_parent)
+      lab= m_parent->last_label();
+    return lab;
   }
 
   inline sp_label_t *
@@ -236,21 +236,15 @@ class sp_pcontext : public Sql_alloc
   }
 
   inline uint
-  handlers()
-  {
-    return m_handlers;
-  }
-
-  inline void
-  push_handlers(uint count)
+  max_handlers()
   {
-    m_hndlrlev+= count;
+    return m_hsubsize + m_handlers;
   }
 
   inline void
-  pop_handlers(uint count)
+  push_handlers(uint n)
   {
-    m_hndlrlev-= count;
+    m_handlers+= n;
   }
 
   //
@@ -263,48 +257,41 @@ class sp_pcontext : public Sql_alloc
   my_bool
   find_cursor(LEX_STRING *name, uint *poff, my_bool scoped=0);
 
-  inline void
-  pop_cursor(uint num)
+  inline uint
+  max_cursors()
   {
-    while (num--)
-      pop_dynamic(&m_cursor);
+    return m_csubsize + m_cursor.elements;
   }
 
   inline uint
-  cursors()
+  current_cursors()
   {
-    return m_cursmax;
+    return m_coffset + m_cursor.elements;
   }
 
-  //
-  // GOTO labels
-  //
+protected:
 
-  sp_label_t *
-  push_glabel(char *name, uint ip);
-
-  sp_label_t *
-  find_glabel(char *name);
-
-  void
-  pop_glabel(uint count);
+  // The maximum sub context's framesizes
+  uint m_psubsize;		
+  uint m_csubsize;
+  uint m_hsubsize;
 
 private:
 
-  uint m_params;		// The number of parameters
-  uint m_framesize;		// The maximum framesize
-  uint m_handlers;		// The total number of handlers
-  uint m_cursmax;		// The maximum number of cursors
-  uint m_hndlrlev;		// Current number of active handlers
+  sp_pcontext *m_parent;	// Parent context
+
+  uint m_poffset;		// Variable offset for this context
+  uint m_coffset;		// Cursor offset for this context
+  uint m_handlers;		// No. of handlers in this context
 
   DYNAMIC_ARRAY m_pvar;		// Parameters/variables
   DYNAMIC_ARRAY m_cond;		// Conditions
   DYNAMIC_ARRAY m_cursor;	// Cursors
-  DYNAMIC_ARRAY m_scopes;	// For error checking
-  DYNAMIC_ARRAY m_glabel;	// Goto labels
 
   List<sp_label_t> m_label;	// The label list
 
+  List<sp_pcontext> m_children;	// Children contexts, used for destruction
+
 }; // class sp_pcontext : public Sql_alloc
 
 

sql/sql_yacc.yy

@@ -1169,7 +1169,6 @@ create:
 	    LEX *lex= Lex;
 
 	    lex->sphead->m_param_end= lex->tok_start;
-	    lex->spcont->set_params();
 	    bzero((char *)&lex->sp_chistics, sizeof(st_sp_chistics));
 	  }
 	  sp_c_chistics
@@ -1258,7 +1257,6 @@ create_function_tail:
 	  {
 	    LEX *lex= Lex;
 
-	    lex->spcont->set_params();
 	    lex->sphead->m_param_end= lex->tok_start;
 	  }
 	  RETURNS_SYM
@@ -1470,25 +1468,28 @@ sp_decl:
 	  DECLARE_SYM sp_decl_idents type sp_opt_default
 	  {
 	    LEX *lex= Lex;
-	    uint max= lex->spcont->current_framesize();
+	    sp_pcontext *ctx= lex->spcont;
+	    uint max= ctx->context_pvars();
 	    enum enum_field_types type= (enum enum_field_types)$3;
 	    Item *it= $4;
 
 	    for (uint i = max-$2 ; i < max ; i++)
 	    {
-	      lex->spcont->set_type(i, type);
+	      ctx->set_type(i, type);
 	      if (! it)
-	        lex->spcont->set_isset(i, FALSE);
+	        ctx->set_isset(i, FALSE);
 	      else
 	      {
 	        sp_instr_set *in= new sp_instr_set(lex->sphead->instructions(),
-	                                           i, it, type);
+	                                           ctx,
+						   ctx->pvar_context2index(i),
+						   it, type);
 
 		in->tables= lex->query_tables;
 		lex->query_tables= 0;
 	        lex->sphead->add_instr(in);
-	        lex->spcont->set_isset(i, TRUE);
-		lex->spcont->set_default(i, it);
+	        ctx->set_isset(i, TRUE);
+		ctx->set_default(i, it);
 	      }
 	    }
 	    $$.vars= $2;
@@ -1514,30 +1515,33 @@ sp_decl:
 	    sp_head *sp= lex->sphead;
 	    sp_pcontext *ctx= lex->spcont;
 	    sp_instr_hpush_jump *i=
-              new sp_instr_hpush_jump(sp->instructions(), $2,
-	                              ctx->current_framesize());
+              new sp_instr_hpush_jump(sp->instructions(), ctx, $2,
+	                              ctx->current_pvars());
 
 	    sp->add_instr(i);
 	    sp->push_backpatch(i, ctx->push_label((char *)"", 0));
 	    ctx->add_handler();
+	    sp->m_in_handler= TRUE;
 	  }
 	  sp_hcond_list sp_proc_stmt
 	  {
 	    LEX *lex= Lex;
 	    sp_head *sp= lex->sphead;
+	    sp_pcontext *ctx= lex->spcont;
 	    sp_label_t *hlab= lex->spcont->pop_label(); /* After this hdlr */
 
 	    if ($2 == SP_HANDLER_CONTINUE)
-	      sp->add_instr(new sp_instr_hreturn(sp->instructions(),
-	                                         lex->spcont->current_framesize()));
+	      sp->add_instr(new sp_instr_hreturn(sp->instructions(), ctx,
+	                                         ctx->current_pvars()));
 	    else
 	    {  /* EXIT or UNDO handler, just jump to the end of the block */
-	      sp_instr_jump *i= new sp_instr_jump(sp->instructions());
+	      sp_instr_jump *i= new sp_instr_jump(sp->instructions(), ctx);
 
 	      sp->add_instr(i);
 	      sp->push_backpatch(i, lex->spcont->last_label()); /* Block end */
 	    }
 	    lex->sphead->backpatch(hlab);
+	    sp->m_in_handler= FALSE;
 	    $$.vars= $$.conds= $$.curs= 0;
 	    $$.hndlrs= $6;
 	  }
@@ -1545,19 +1549,19 @@ sp_decl:
 	  {
 	    LEX *lex= Lex;
 	    sp_head *sp= lex->sphead;
-	    sp_pcontext *spc= lex->spcont;
+	    sp_pcontext *ctx= lex->spcont;
 	    uint offp;
 	    sp_instr_cpush *i;
 
-	    if (spc->find_cursor(&$2, &offp, TRUE))
+	    if (ctx->find_cursor(&$2, &offp, TRUE))
 	    {
 	      net_printf(YYTHD, ER_SP_DUP_CURS, $2.str);
 	      delete $5;
 	      YYABORT;
 	    }
-            i= new sp_instr_cpush(sp->instructions(), $5);
+            i= new sp_instr_cpush(sp->instructions(), ctx, $5);
 	    sp->add_instr(i);
-	    lex->spcont->push_cursor(&$2);
+	    ctx->push_cursor(&$2);
 	    $$.vars= $$.conds= $$.hndlrs= 0;
 	    $$.curs= 1;
 	  }
@@ -1748,7 +1752,8 @@ sp_proc_stmt:
 	      }
 	      else
 	      {
-		sp_instr_stmt *i=new sp_instr_stmt(lex->sphead->instructions());
+		sp_instr_stmt *i=new sp_instr_stmt(lex->sphead->instructions(),
+						   lex->spcont);
 
 		i->set_lex(lex);
 		lex->sphead->add_instr(i);
@@ -1776,6 +1781,7 @@ sp_proc_stmt:
 	        YYABORT;
 	      }
 	      i= new sp_instr_freturn(lex->sphead->instructions(),
+				      lex->spcont,
 		                      $2, lex->sphead->m_returns);
 	      lex->sphead->add_instr(i);
 	      lex->sphead->m_has_return= TRUE;
@@ -1794,8 +1800,9 @@ sp_proc_stmt:
 	       at the same frame level, so we then know that it's the
 	       top-most variable in the frame. */
 	    LEX *lex= Lex;
-	    uint offset= lex->spcont->current_framesize();
+	    uint offset= lex->spcont->current_pvars();
 	    sp_instr_set *i = new sp_instr_set(lex->sphead->instructions(),
+					       lex->spcont,
 	                                       offset, $2, MYSQL_TYPE_STRING);
 	    LEX_STRING dummy;
 
@@ -1839,19 +1846,17 @@ sp_proc_stmt:
 	    else
 	    {
 	      uint ip= sp->instructions();
-	      sp_scope_t sdiff;
 	      sp_instr_jump *i;
 	      sp_instr_hpop *ih;
 	      sp_instr_cpop *ic;
 
-	      ctx->diff_scopes(0, &sdiff);
-	      ih= new sp_instr_hpop(ip++, sdiff.hndlrs);
+	      ih= new sp_instr_hpop(ip++, ctx, 0);
 	      sp->push_backpatch(ih, lab);
 	      sp->add_instr(ih);
-	      ic= new sp_instr_cpop(ip++, sdiff.curs);
+	      ic= new sp_instr_cpop(ip++, ctx, 0);
 	      sp->push_backpatch(ic, lab);
 	      sp->add_instr(ic);
-	      i= new sp_instr_jump(ip);
+	      i= new sp_instr_jump(ip, ctx);
 	      sp->push_backpatch(i, lab);  /* Jumping forward */
               sp->add_instr(i);
 	    }
@@ -1872,14 +1877,15 @@ sp_proc_stmt:
 	    {
 	      sp_instr_jump *i;
 	      uint ip= sp->instructions();
-	      sp_scope_t sdiff;
-
-	      ctx->diff_scopes(lab->scopes, &sdiff);
-	      if (sdiff.hndlrs)
-	        sp->add_instr(new sp_instr_hpop(ip++, sdiff.hndlrs));
-	      if (sdiff.curs)
-	        sp->add_instr(new sp_instr_cpop(ip++, sdiff.curs));
-	      i= new sp_instr_jump(ip, lab->ip); /* Jump back */
+	      uint n;
+
+	      n= ctx->diff_handlers(lab->ctx);
+	      if (n)
+	        sp->add_instr(new sp_instr_hpop(ip++, ctx, n));
+	      n= ctx->diff_cursors(lab->ctx);
+	      if (n)
+	        sp->add_instr(new sp_instr_cpop(ip++, ctx, n));
+	      i= new sp_instr_jump(ip, ctx, lab->ip); /* Jump back */
               sp->add_instr(i);
 	    }
 	  }
@@ -1890,8 +1896,6 @@ sp_proc_stmt:
 	    sp_pcontext *ctx= lex->spcont;
 	    sp_label_t *lab= ctx->find_label($2.str);
 
-	    if (! lab)
-	      lab= ctx->find_glabel($2.str);
 	    if (lab)
 	    {
 	      net_printf(YYTHD, ER_SP_LABEL_REDEFINE, $2.str);
@@ -1899,9 +1903,9 @@ sp_proc_stmt:
 	    }
 	    else
 	    {
-	      lab= ctx->push_glabel($2.str, sp->instructions());
+	      lab= ctx->push_label($2.str, sp->instructions());
 	      lab->type= SP_LAB_GOTO;
-	      lab->scopes= ctx->scopes();
+	      lab->ctx= ctx;
               sp->backpatch(lab);
 	    }
 	  }
@@ -1911,48 +1915,52 @@ sp_proc_stmt:
 	    sp_head *sp= lex->sphead;
 	    sp_pcontext *ctx= lex->spcont;
 	    uint ip= lex->sphead->instructions();
-	    sp_label_t *lab= ctx->find_label($2.str);
-	    sp_scope_t sdiff;
+	    sp_label_t *lab;
 	    sp_instr_jump *i;
 	    sp_instr_hpop *ih;
 	    sp_instr_cpop *ic;
 
-	    if (! lab)
-	      lab= ctx->find_glabel($2.str);
-
+	    if (sp->m_in_handler)
+	    {
+	      send_error(lex->thd, ER_SP_GOTO_IN_HNDLR);
+	      YYABORT;
+	    }
+	    lab= ctx->find_label($2.str);
 	    if (! lab)
 	    {
 	      lab= (sp_label_t *)YYTHD->alloc(sizeof(sp_label_t));
 	      lab->name= $2.str;
 	      lab->ip= 0;
 	      lab->type= SP_LAB_REF;
-	      lab->scopes= 0;
+	      lab->ctx= ctx;
 
-	      ctx->diff_scopes(0, &sdiff);
-	      ih= new sp_instr_hpop(ip++, sdiff.hndlrs);
+	      ih= new sp_instr_hpop(ip++, ctx, 0);
 	      sp->push_backpatch(ih, lab);
 	      sp->add_instr(ih);
-	      ic= new sp_instr_cpop(ip++, sdiff.curs);
+	      ic= new sp_instr_cpop(ip++, ctx, 0);
 	      sp->add_instr(ic);
 	      sp->push_backpatch(ic, lab);
-	      i= new sp_instr_jump(ip);
+	      i= new sp_instr_jump(ip, ctx);
 	      sp->push_backpatch(i, lab);  /* Jumping forward */
 	      sp->add_instr(i);
 	    }
 	    else
 	    {
-	      ctx->diff_scopes(lab->scopes, &sdiff);
-	      if (sdiff.hndlrs)
+	      uint n;
+
+	      n= ctx->diff_handlers(lab->ctx);
+	      if (n)
 	      {
-	        ih= new sp_instr_hpop(ip++, sdiff.hndlrs);
+	        ih= new sp_instr_hpop(ip++, ctx, n);
 	        sp->add_instr(ih);
 	      }
-	      if (sdiff.curs)
+	      n= ctx->diff_cursors(lab->ctx);
+	      if (n)
 	      {
-	        ic= new sp_instr_cpop(ip++, sdiff.curs);
+	        ic= new sp_instr_cpop(ip++, ctx, n);
 	        sp->add_instr(ic);
 	      }
-	      i= new sp_instr_jump(ip, lab->ip); /* Jump back */
+	      i= new sp_instr_jump(ip, ctx, lab->ip); /* Jump back */
 	      sp->add_instr(i);
 	    }
 	  }
@@ -1968,7 +1976,7 @@ sp_proc_stmt:
 	      net_printf(YYTHD, ER_SP_CURSOR_MISMATCH, $2.str);
 	      YYABORT;
 	    }
-	    i= new sp_instr_copen(sp->instructions(), offset);
+	    i= new sp_instr_copen(sp->instructions(), lex->spcont, offset);
 	    sp->add_instr(i);
 	  }
 	| FETCH_SYM ident INTO
@@ -1983,7 +1991,7 @@ sp_proc_stmt:
 	      net_printf(YYTHD, ER_SP_CURSOR_MISMATCH, $2.str);
 	      YYABORT;
 	    }
-	    i= new sp_instr_cfetch(sp->instructions(), offset);
+	    i= new sp_instr_cfetch(sp->instructions(), lex->spcont, offset);
 	    sp->add_instr(i);
 	  }
 	  sp_fetch_list
@@ -2000,7 +2008,7 @@ sp_proc_stmt:
 	      net_printf(YYTHD, ER_SP_CURSOR_MISMATCH, $2.str);
 	      YYABORT;
 	    }
-	    i= new sp_instr_cclose(sp->instructions(), offset);
+	    i= new sp_instr_cclose(sp->instructions(), lex->spcont,  offset);
 	    sp->add_instr(i);
 	  }
 	;
@@ -2056,7 +2064,7 @@ sp_if:
 	    sp_head *sp= lex->sphead;
 	    sp_pcontext *ctx= lex->spcont;
 	    uint ip= sp->instructions();
-	    sp_instr_jump_if_not *i = new sp_instr_jump_if_not(ip, $1);
+	    sp_instr_jump_if_not *i = new sp_instr_jump_if_not(ip, ctx, $1);
 
 	    i->tables= lex->query_tables;
 	    lex->query_tables= 0;
@@ -2068,7 +2076,7 @@ sp_if:
 	    sp_head *sp= Lex->sphead;
 	    sp_pcontext *ctx= Lex->spcont;
 	    uint ip= sp->instructions();
-	    sp_instr_jump *i = new sp_instr_jump(ip);
+	    sp_instr_jump *i = new sp_instr_jump(ip, ctx);
 
 	    sp->add_instr(i);
 	    sp->backpatch(ctx->pop_label());
@@ -2098,7 +2106,7 @@ sp_case:
 	    sp_instr_jump_if_not *i;
 
 	    if (! sp->m_simple_case)
-	      i= new sp_instr_jump_if_not(ip, $1);
+	      i= new sp_instr_jump_if_not(ip, ctx, $1);
 	    else
 	    { /* Simple case: <caseval> = <whenval> */
 	      LEX_STRING ivar;
@@ -2106,10 +2114,10 @@ sp_case:
 	      ivar.str= (char *)"_tmp_";
 	      ivar.length= 5;
 	      Item *var= (Item*) new Item_splocal(ivar, 
-						  ctx->current_framesize()-1);
+						  ctx->current_pvars()-1);
 	      Item *expr= new Item_func_eq(var, $1);
 
-	      i= new sp_instr_jump_if_not(ip, expr);
+	      i= new sp_instr_jump_if_not(ip, ctx, expr);
               lex->variables_used= 1;
 	    }
 	    sp->push_backpatch(i, ctx->push_label((char *)"", 0));
@@ -2122,7 +2130,7 @@ sp_case:
 	    sp_head *sp= Lex->sphead;
 	    sp_pcontext *ctx= Lex->spcont;
 	    uint ip= sp->instructions();
-	    sp_instr_jump *i = new sp_instr_jump(ip);
+	    sp_instr_jump *i = new sp_instr_jump(ip, ctx);
 
 	    sp->add_instr(i);
 	    sp->backpatch(ctx->pop_label());
@@ -2141,7 +2149,8 @@ sp_whens:
 	  {
 	    sp_head *sp= Lex->sphead;
 	    uint ip= sp->instructions();
-	    sp_instr_error *i= new sp_instr_error(ip, ER_SP_CASE_NOT_FOUND);
+	    sp_instr_error *i= new sp_instr_error(ip, Lex->spcont,
+						  ER_SP_CASE_NOT_FOUND);
 
 	    sp->add_instr(i);
 	  }
@@ -2166,7 +2175,6 @@ sp_labeled_control:
 	      lab= lex->spcont->push_label($1.str,
 	                                   lex->sphead->instructions());
 	      lab->type= SP_LAB_ITER;
-	      lab->scopes= ctx->scopes();
 	    }
 	  }
 	  sp_unlabeled_control sp_opt_label
@@ -2204,32 +2212,24 @@ sp_unlabeled_control:
 	    sp_label_t *lab= lex->spcont->last_label();
 
 	    lab->type= SP_LAB_BEGIN;
-	    /* Scope duplicate checking */
-	    lex->spcont->push_scope();
+	    lex->spcont= lex->spcont->push_context();
 	  }
 	  sp_decls
-	  {
-	    Lex->spcont->push_handlers($3.hndlrs);
-	  }
 	  sp_proc_stmts
 	  END
 	  {
 	    LEX *lex= Lex;
 	    sp_head *sp= lex->sphead;
 	    sp_pcontext *ctx= lex->spcont;
-	    sp_scope_t scope;
 
   	    sp->backpatch(ctx->last_label());	/* We always have a label */
-	    ctx->pop_pvar($3.vars);
-	    ctx->pop_cond($3.conds);
-	    ctx->pop_handlers($3.hndlrs);
-	    ctx->pop_cursor($3.curs);
 	    if ($3.hndlrs)
-	      sp->add_instr(new sp_instr_hpop(sp->instructions(), $3.hndlrs));
+	      sp->add_instr(new sp_instr_hpop(sp->instructions(), ctx,
+					      $3.hndlrs));
 	    if ($3.curs)
-	      sp->add_instr(new sp_instr_cpop(sp->instructions(), $3.curs));
-	    ctx->pop_scope(&scope);
-	    ctx->pop_glabel(scope.glab);
+	      sp->add_instr(new sp_instr_cpop(sp->instructions(), ctx,
+					      $3.curs));
+	    lex->spcont= ctx->pop_context();
 	  }
 	| LOOP_SYM
 	  sp_proc_stmts END LOOP_SYM
@@ -2237,7 +2237,7 @@ sp_unlabeled_control:
 	    LEX *lex= Lex;
 	    uint ip= lex->sphead->instructions();
 	    sp_label_t *lab= lex->spcont->last_label();  /* Jumping back */
-	    sp_instr_jump *i = new sp_instr_jump(ip, lab->ip);
+	    sp_instr_jump *i = new sp_instr_jump(ip, lex->spcont, lab->ip);
 
 	    lex->sphead->add_instr(i);
 	  }
@@ -2246,7 +2246,8 @@ sp_unlabeled_control:
 	    LEX *lex= Lex;
 	    sp_head *sp= lex->sphead;
 	    uint ip= sp->instructions();
-	    sp_instr_jump_if_not *i = new sp_instr_jump_if_not(ip, $2);
+	    sp_instr_jump_if_not *i = new sp_instr_jump_if_not(ip, lex->spcont,
+							       $2);
 
 	    /* Jumping forward */
 	    sp->push_backpatch(i, lex->spcont->last_label());
@@ -2259,7 +2260,7 @@ sp_unlabeled_control:
 	    LEX *lex= Lex;
 	    uint ip= lex->sphead->instructions();
 	    sp_label_t *lab= lex->spcont->last_label();  /* Jumping back */
-	    sp_instr_jump *i = new sp_instr_jump(ip, lab->ip);
+	    sp_instr_jump *i = new sp_instr_jump(ip, lex->spcont, lab->ip);
 
 	    lex->sphead->add_instr(i);
 	  }
@@ -2268,7 +2269,8 @@ sp_unlabeled_control:
 	    LEX *lex= Lex;
 	    uint ip= lex->sphead->instructions();
 	    sp_label_t *lab= lex->spcont->last_label();  /* Jumping back */
-	    sp_instr_jump_if_not *i = new sp_instr_jump_if_not(ip, $4, lab->ip);
+	    sp_instr_jump_if_not *i = new sp_instr_jump_if_not(ip, lex->spcont,
+							       $4, lab->ip);
 
 	    i->tables= lex->query_tables;
 	    lex->query_tables= 0;
@@ -6786,11 +6788,12 @@ option_value:
 	    }
             else
 	    { /* An SP local variable */
+	      sp_pcontext *ctx= lex->spcont;
 	      sp_pvar_t *spv;
               sp_instr_set *i;
 	      Item *it;
 
-	      spv= lex->spcont->find_pvar(&$1.base_name);
+	      spv= ctx->find_pvar(&$1.base_name);
 
 	      if ($3)
 	        it= $3;
@@ -6798,7 +6801,7 @@ option_value:
 	        it= spv->dflt;
 	      else
 	        it= new Item_null();
-              i= new sp_instr_set(lex->sphead->instructions(),
+              i= new sp_instr_set(lex->sphead->instructions(), ctx,
 	                          spv->offset, it, spv->type);
 	      i->tables= lex->query_tables;
 	      lex->query_tables= 0;