Bug#35577 (CREATE PROCEDURE causes either crash or syntax error depending on

build)

The crash was caused by freeing the internal parser stack during the parser
execution.
This occured only for complex stored procedures, after reallocating the parser
stack using my_yyoverflow(), with the following C call stack:
- MYSQLparse()
- any rule calling sp_head::restore_lex()
- lex_end()
- x_free(lex->yacc_yyss), xfree(lex->yacc_yyvs)

The root cause is the implementation of stored procedures, which breaks the
assumption from 4.1 that there is only one LEX structure per parser call.

The solution is to separate the LEX structure into:
- attributes that represent a statement (the current LEX structure),
- attributes that relate to the syntax parser itself (Yacc_state),
so that parsing multiple statements in stored programs can create multiple
LEX structures while not changing the unique Yacc_state.

Now, Yacc_state and the existing Lex_input_stream are aggregated into
Parser_state, a structure that represent the complete state of the (Lexical +
Syntax) parser.


mysql-test/r/parser_stack.result:
  Bug#35577 (CREATE PROCEDURE causes either crash or syntax error depending on
  build)
mysql-test/t/parser_stack.test:
  Bug#35577 (CREATE PROCEDURE causes either crash or syntax error depending on
  build)
sql/sp.cc:
  Bug#35577 (CREATE PROCEDURE causes either crash or syntax error depending on
  build)
sql/sp_head.cc:
  Bug#35577 (CREATE PROCEDURE causes either crash or syntax error depending on
  build)
sql/sql_class.cc:
  Bug#35577 (CREATE PROCEDURE causes either crash or syntax error depending on
  build)
sql/sql_class.h:
  Bug#35577 (CREATE PROCEDURE causes either crash or syntax error depending on
  build)
sql/sql_lex.cc:
  Bug#35577 (CREATE PROCEDURE causes either crash or syntax error depending on
  build)
sql/sql_lex.h:
  Bug#35577 (CREATE PROCEDURE causes either crash or syntax error depending on
  build)
sql/sql_parse.cc:
  Bug#35577 (CREATE PROCEDURE causes either crash or syntax error depending on
  build)
sql/sql_prepare.cc:
  Bug#35577 (CREATE PROCEDURE causes either crash or syntax error depending on
  build)
sql/sql_trigger.cc:
  Bug#35577 (CREATE PROCEDURE causes either crash or syntax error depending on
  build)
sql/sql_view.cc:
  Bug#35577 (CREATE PROCEDURE causes either crash or syntax error depending on
  build)
sql/sql_yacc.yy:
  Bug#35577 (CREATE PROCEDURE causes either crash or syntax error depending on
  build)

11 files changed, 140 insertions, 84 deletions

diff --git a/sql/sp.cc b/sql/sp.cc
index 2392cabb220..d2a12f2190f 100644
--- a/sql/sp.cc
+++ b/sql/sp.cc
@@ -443,11 +443,12 @@ db_load_routine(THD *thd, int type, sp_name *name, sp_head **sphp,
     goto end;
 
   {
-    Lex_input_stream lip(thd, defstr.c_ptr(), defstr.length());
-    thd->m_lip= &lip;
+    Parser_state parser_state(thd, defstr.c_ptr(), defstr.length());
+    thd->m_parser_state= &parser_state;
     lex_start(thd);
     thd->spcont= NULL;
     ret= MYSQLparse(thd);
+    thd->m_parser_state= NULL;
 
     if (ret == 0)
     {
diff --git a/sql/sp_head.cc b/sql/sp_head.cc
index aea81e301ef..2d920598c46 100644
--- a/sql/sp_head.cc
+++ b/sql/sp_head.cc
@@ -591,7 +591,7 @@ sp_head::init_strings(THD *thd, LEX *lex)
   const char *endp;                  /* Used to trim the end */
   /* During parsing, we must use thd->mem_root */
   MEM_ROOT *root= thd->mem_root;
-  Lex_input_stream *lip=thd->m_lip;
+  Lex_input_stream *lip= & thd->m_parser_state->m_lip;
 
   if (m_param_begin && m_param_end)
   {
diff --git a/sql/sql_class.cc b/sql/sql_class.cc
index f541c8b3677..6fd11e340be 100644
--- a/sql/sql_class.cc
+++ b/sql/sql_class.cc
@@ -177,7 +177,8 @@ THD::THD()
    rand_used(0), time_zone_used(0),
    last_insert_id_used(0), last_insert_id_used_bin_log(0), insert_id_used(0),
    clear_next_insert_id(0), in_lock_tables(0), bootstrap(0),
-   derived_tables_processing(FALSE), spcont(NULL), m_lip(NULL)
+   derived_tables_processing(FALSE), spcont(NULL),
+   m_parser_state(NULL)
 {
   ulong tmp;
 
diff --git a/sql/sql_class.h b/sql/sql_class.h
index 4ca8947de30..77ef868a5c6 100644
--- a/sql/sql_class.h
+++ b/sql/sql_class.h
@@ -28,7 +28,7 @@ class Slave_log_event;
 class Format_description_log_event;
 class sp_rcontext;
 class sp_cache;
-class Lex_input_stream;
+class Parser_state;
 
 enum enum_enable_or_disable { LEAVE_AS_IS, ENABLE, DISABLE };
 enum enum_ha_read_modes { RFIRST, RNEXT, RPREV, RLAST, RKEY, RNEXT_SAME };
@@ -1575,13 +1575,11 @@ public:
   } binlog_evt_union;
 
   /**
-    Character input stream consumed by the lexical analyser,
-    used during parsing.
-    Note that since the parser is not re-entrant, we keep only one input
-    stream here. This member is valid only when executing code during parsing,
-    and may point to invalid memory after that.
+    Internal parser state.
+    Note that since the parser is not re-entrant, we keep only one parser
+    state here. This member is valid only when executing code during parsing.
   */
-  Lex_input_stream *m_lip;
+  Parser_state *m_parser_state;
 
   THD();
   ~THD();
diff --git a/sql/sql_lex.cc b/sql/sql_lex.cc
index a1bfc3edc6c..0cf7c11b447 100644
--- a/sql/sql_lex.cc
+++ b/sql/sql_lex.cc
@@ -192,7 +192,6 @@ void lex_start(THD *thd)
   lex->select_lex.order_list.empty();
   lex->select_lex.udf_list.empty();
   lex->current_select= &lex->select_lex;
-  lex->yacc_yyss=lex->yacc_yyvs=0;
   lex->sql_command= lex->orig_sql_command= SQLCOM_END;
   lex->duplicates= DUP_ERROR;
   lex->ignore= 0;
@@ -210,11 +209,16 @@ void lex_start(THD *thd)
 
 void lex_end(LEX *lex)
 {
-  DBUG_ENTER("lex_end");
-  DBUG_PRINT("enter", ("lex: 0x%lx", (long) lex));
-  x_free(lex->yacc_yyss);
-  x_free(lex->yacc_yyvs);
-  DBUG_VOID_RETURN;
+  /* Empty in 5.0, non empty in 5.1 */
+}
+
+Yacc_state::~Yacc_state()
+{
+  if (yacc_yyss)
+  {
+    x_free(yacc_yyss);
+    x_free(yacc_yyvs);
+  }
 }
 
 
@@ -531,7 +535,7 @@ int MYSQLlex(void *arg, void *yythd)
   uint length;
   enum my_lex_states state;
   THD *thd= (THD *)yythd;
-  Lex_input_stream *lip= thd->m_lip;
+  Lex_input_stream *lip= & thd->m_parser_state->m_lip;
   LEX *lex= thd->lex;
   YYSTYPE *yylval=(YYSTYPE*) arg;
   CHARSET_INFO *cs= thd->charset();
@@ -1781,7 +1785,7 @@ void Query_tables_list::destroy_query_tables_list()
 */
 
 st_lex::st_lex()
-  :result(0), yacc_yyss(0), yacc_yyvs(0),
+  :result(0),
    sql_command(SQLCOM_END)
 {
   reset_query_tables_list(TRUE);
diff --git a/sql/sql_lex.h b/sql/sql_lex.h
index cde4c3a97b3..df0db2e209d 100644
--- a/sql/sql_lex.h
+++ b/sql/sql_lex.h
@@ -1004,7 +1004,6 @@ typedef struct st_lex : public Query_tables_list
   LEX_STRING comment, ident;
   LEX_USER *grant_user;
   XID *xid;
-  gptr yacc_yyss,yacc_yyvs;
   THD *thd;
   CHARSET_INFO *charset, *underscore_charset;
   bool text_string_is_7bit;
@@ -1290,6 +1289,59 @@ typedef struct st_lex : public Query_tables_list
   }
 } LEX;
 
+
+/**
+  The internal state of the syntax parser.
+  This object is only available during parsing,
+  and is private to the syntax parser implementation (sql_yacc.yy).
+*/
+class Yacc_state
+{
+public:
+  Yacc_state()
+    : yacc_yyss(NULL), yacc_yyvs(NULL)
+  {}
+
+  ~Yacc_state();
+
+  /**
+    Bison internal state stack, yyss, when dynamically allocated using
+    my_yyoverflow().
+  */
+  gptr yacc_yyss;
+
+  /**
+    Bison internal semantic value stack, yyvs, when dynamically allocated using
+    my_yyoverflow().
+  */
+  gptr yacc_yyvs;
+
+  /*
+    TODO: move more attributes from the LEX structure here.
+  */
+};
+
+/**
+  Internal state of the parser.
+  The complete state consist of:
+  - state data used during lexical parsing,
+  - state data used during syntactic parsing.
+*/
+class Parser_state
+{
+public:
+  Parser_state(THD *thd, const char* buff, unsigned int length)
+    : m_lip(thd, buff, length), m_yacc()
+  {}
+
+  ~Parser_state()
+  {}
+
+  Lex_input_stream m_lip;
+  Yacc_state m_yacc;
+};
+
+
 struct st_lex_local: public st_lex
 {
   static void *operator new(size_t size) throw()
diff --git a/sql/sql_parse.cc b/sql/sql_parse.cc
index 62a5a79a833..58b942f21d2 100644
--- a/sql/sql_parse.cc
+++ b/sql/sql_parse.cc
@@ -5875,29 +5875,35 @@ bool check_stack_overrun(THD *thd, long margin,
 
 bool my_yyoverflow(short **yyss, YYSTYPE **yyvs, ulong *yystacksize)
 {
-  LEX	*lex= current_thd->lex;
+  Yacc_state *state= & current_thd->m_parser_state->m_yacc;
   ulong old_info=0;
+  DBUG_ASSERT(state);
   if ((uint) *yystacksize >= MY_YACC_MAX)
     return 1;
-  if (!lex->yacc_yyvs)
+  if (!state->yacc_yyvs)
     old_info= *yystacksize;
   *yystacksize= set_zone((*yystacksize)*2,MY_YACC_INIT,MY_YACC_MAX);
-  if (!(lex->yacc_yyvs= (char*)
-	my_realloc((gptr) lex->yacc_yyvs,
+  if (!(state->yacc_yyvs= (char*)
+        my_realloc(state->yacc_yyvs,
 		   *yystacksize*sizeof(**yyvs),
 		   MYF(MY_ALLOW_ZERO_PTR | MY_FREE_ON_ERROR))) ||
-      !(lex->yacc_yyss= (char*)
-	my_realloc((gptr) lex->yacc_yyss,
+      !(state->yacc_yyss= (char*)
+        my_realloc(state->yacc_yyss,
 		   *yystacksize*sizeof(**yyss),
 		   MYF(MY_ALLOW_ZERO_PTR | MY_FREE_ON_ERROR))))
     return 1;
   if (old_info)
-  {						// Copy old info from stack
-    memcpy(lex->yacc_yyss, (gptr) *yyss, old_info*sizeof(**yyss));
-    memcpy(lex->yacc_yyvs, (gptr) *yyvs, old_info*sizeof(**yyvs));
+  {
+    /*
+      Only copy the old stack on the first call to my_yyoverflow(),
+      when replacing a static stack (YYINITDEPTH) by a dynamic stack.
+      For subsequent calls, my_realloc already did preserve the old stack.
+    */
+    memcpy(state->yacc_yyss, *yyss, old_info*sizeof(**yyss));
+    memcpy(state->yacc_yyvs, *yyvs, old_info*sizeof(**yyvs));
   }
-  *yyss=(short*) lex->yacc_yyss;
-  *yyvs=(YYSTYPE*) lex->yacc_yyvs;
+  *yyss= (short*) state->yacc_yyss;
+  *yyvs= (YYSTYPE*) state->yacc_yyvs;
   return 0;
 }
 
@@ -6136,11 +6142,12 @@ void mysql_parse(THD *thd, const char *inBuf, uint length,
     sp_cache_flush_obsolete(&thd->sp_proc_cache);
     sp_cache_flush_obsolete(&thd->sp_func_cache);
 
-    Lex_input_stream lip(thd, inBuf, length);
-    thd->m_lip= &lip;
+    Parser_state parser_state(thd, inBuf, length);
+    thd->m_parser_state= &parser_state;
 
     int err= MYSQLparse(thd);
-    *found_semicolon= lip.found_semicolon;
+    *found_semicolon= parser_state.m_lip.found_semicolon;
+    thd->m_parser_state= NULL;
 
     if (!err && ! thd->is_fatal_error)
     {
@@ -6165,8 +6172,9 @@ void mysql_parse(THD *thd, const char *inBuf, uint length,
             PROCESSLIST.
             Note that we don't need LOCK_thread_count to modify query_length.
           */
-          if (lip.found_semicolon &&
-              (thd->query_length= (ulong)(lip.found_semicolon - thd->query)))
+          if (parser_state.m_lip.found_semicolon &&
+              (thd->query_length= (ulong)(parser_state.m_lip.found_semicolon
+                                          - thd->query)))
             thd->query_length--;
           /* Actually execute the query */
           if (*found_semicolon)
@@ -6225,11 +6233,13 @@ bool mysql_test_parse_for_slave(THD *thd, char *inBuf, uint length)
   bool error= 0;
   DBUG_ENTER("mysql_test_parse_for_slave");
 
-  Lex_input_stream lip(thd, inBuf, length);
-  thd->m_lip= &lip;
+  Parser_state parser_state(thd, inBuf, length);
+  thd->m_parser_state= &parser_state;
+
   lex_start(thd);
   mysql_reset_thd_for_next_command(thd);
   int err= MYSQLparse((void*) thd);
+  thd->m_parser_state= NULL;
 
   if (!err && ! thd->is_fatal_error &&
       all_tables_not_ok(thd,(TABLE_LIST*) lex->select_lex.table_list.first))
@@ -7295,7 +7305,7 @@ bool check_simple_select()
   if (lex->current_select != &lex->select_lex)
   {
     char command[80];
-    Lex_input_stream *lip= thd->m_lip;
+    Lex_input_stream *lip= & thd->m_parser_state->m_lip;
     strmake(command, lip->yylval->symbol.str,
 	    min(lip->yylval->symbol.length, sizeof(command)-1));
     my_error(ER_CANT_USE_OPTION_HERE, MYF(0), command);
diff --git a/sql/sql_prepare.cc b/sql/sql_prepare.cc
index e7855946179..9e144f5ae9b 100644
--- a/sql/sql_prepare.cc
+++ b/sql/sql_prepare.cc
@@ -2849,12 +2849,13 @@ bool Prepared_statement::prepare(const char *packet, uint packet_len)
   old_stmt_arena= thd->stmt_arena;
   thd->stmt_arena= this;
 
-  Lex_input_stream lip(thd, thd->query, thd->query_length);
-  lip.stmt_prepare_mode= TRUE;
-  thd->m_lip= &lip;
+  Parser_state parser_state(thd, thd->query, thd->query_length);
+  parser_state.m_lip.stmt_prepare_mode= TRUE;
+  thd->m_parser_state= &parser_state;
   lex_start(thd);
   lex->safe_to_cache_query= FALSE;
   int err= MYSQLparse((void *)thd);
+  thd->m_parser_state= NULL;
   lex->set_trg_event_type_for_tables();
 
   error= err || thd->is_fatal_error ||
diff --git a/sql/sql_trigger.cc b/sql/sql_trigger.cc
index 1737bb0d9f8..bead50e1da8 100644
--- a/sql/sql_trigger.cc
+++ b/sql/sql_trigger.cc
@@ -968,11 +968,13 @@ bool Table_triggers_list::check_n_load(THD *thd, const char *db,
 
         thd->variables.sql_mode= (ulong)*trg_sql_mode;
 
-        Lex_input_stream lip(thd, trg_create_str->str, trg_create_str->length);
-        thd->m_lip= &lip;
+        Parser_state parser_state(thd, trg_create_str->str,
+                                  trg_create_str->length);
+        thd->m_parser_state= &parser_state;
         lex_start(thd);
         thd->spcont= NULL;
         int err= MYSQLparse((void *)thd);
+        thd->m_parser_state= NULL;
 
         if (err || thd->is_fatal_error)
         {
diff --git a/sql/sql_view.cc b/sql/sql_view.cc
index de92d6dc3b9..3b5fd6a085b 100644
--- a/sql/sql_view.cc
+++ b/sql/sql_view.cc
@@ -1081,8 +1081,7 @@ bool mysql_make_view(THD *thd, File_parser *parser, TABLE_LIST *table,
     char old_db_buf[NAME_LEN+1];
     LEX_STRING old_db= { old_db_buf, sizeof(old_db_buf) };
     bool dbchanged;
-    Lex_input_stream lip(thd, table->query.str, table->query.length);
-    thd->m_lip= &lip;
+    Parser_state parser_state(thd, table->query.str, table->query.length);
 
     /* 
       Use view db name as thread default database, in order to ensure
@@ -1091,6 +1090,7 @@ bool mysql_make_view(THD *thd, File_parser *parser, TABLE_LIST *table,
     if ((result= sp_use_new_db(thd, table->view_db, &old_db, 1, &dbchanged)))
       goto end;
 
+    thd->m_parser_state= &parser_state;
     lex_start(thd);
     view_select= &lex->select_lex;
     view_select->select_number= ++thd->select_number;
@@ -1125,6 +1125,7 @@ bool mysql_make_view(THD *thd, File_parser *parser, TABLE_LIST *table,
     CHARSET_INFO *save_cs= thd->variables.character_set_client;
     thd->variables.character_set_client= system_charset_info;
     res= MYSQLparse((void *)thd);
+    thd->m_parser_state= NULL;
 
     if ((old_lex->sql_command == SQLCOM_SHOW_FIELDS) ||
         (old_lex->sql_command == SQLCOM_SHOW_CREATE))
diff --git a/sql/sql_yacc.yy b/sql/sql_yacc.yy
index 090585392a0..39851ac66f8 100644
--- a/sql/sql_yacc.yy
+++ b/sql/sql_yacc.yy
@@ -23,6 +23,7 @@
 #define YYPARSE_PARAM yythd
 #define YYLEX_PARAM yythd
 #define YYTHD ((THD *)yythd)
+#define YYLIP (& YYTHD->m_parser_state->m_lip)
 
 #define MYSQL_YACC
 #define YYINITDEPTH 100
@@ -86,7 +87,7 @@ const LEX_STRING null_lex_str={0,0};
 void my_parse_error(const char *s)
 {
   THD *thd= current_thd;
-  Lex_input_stream *lip= thd->m_lip;
+  Lex_input_stream *lip= & thd->m_parser_state->m_lip;
 
   const char *yytext= lip->tok_start;
   /* Push an error into the error stack */
@@ -1213,11 +1214,11 @@ query:
               MYSQL_YYABORT;
             }
             thd->lex->sql_command= SQLCOM_EMPTY_QUERY;
-            thd->m_lip->found_semicolon= NULL;
+            YYLIP->found_semicolon= NULL;
           }
         | verb_clause
           {
-            Lex_input_stream *lip = YYTHD->m_lip;
+            Lex_input_stream *lip = YYLIP;
 
             if ((YYTHD->client_capabilities & CLIENT_MULTI_QUERIES) &&
                 ! lip->stmt_prepare_mode &&
@@ -1243,7 +1244,7 @@ query:
         | verb_clause END_OF_INPUT
           {
             /* Single query, not terminated. */
-            YYTHD->m_lip->found_semicolon= NULL;
+            YYLIP->found_semicolon= NULL;
           }
         ;
 
@@ -2155,7 +2156,7 @@ sp_proc_stmt:
 	  {
             THD *thd= YYTHD;
 	    LEX *lex= thd->lex;
-            Lex_input_stream *lip= thd->m_lip;
+            Lex_input_stream *lip= YYLIP;
 
 	    if (lex->sphead->reset_lex(thd))
               MYSQL_YYABORT;
@@ -2165,7 +2166,7 @@ sp_proc_stmt:
 	  {
             THD *thd= YYTHD;
 	    LEX *lex= thd->lex;
-            Lex_input_stream *lip= thd->m_lip;
+            Lex_input_stream *lip= YYLIP;
 	    sp_head *sp= lex->sphead;
 
             sp->m_flags|= sp_get_flags_for_command(lex);
@@ -4503,16 +4504,12 @@ select_item:
 
 remember_name:
 	{
-          THD *thd= YYTHD;
-          Lex_input_stream *lip= thd->m_lip;
-          $$= (char*) lip->tok_start;
+          $$= (char*) YYLIP->tok_start;
         };
 
 remember_end:
 	{
-          THD *thd= YYTHD;
-          Lex_input_stream *lip= thd->m_lip;
-          $$=(char*) lip->tok_end;
+          $$=(char*) YYLIP->tok_end;
         };
 
 select_item2:
@@ -6452,7 +6449,7 @@ procedure_item:
 	  remember_name expr
 	  {
             THD *thd= YYTHD;
-            Lex_input_stream *lip= thd->m_lip;
+            Lex_input_stream *lip= YYLIP;
 
 	    if (add_proc_to_list(thd, $2))
 	      MYSQL_YYABORT;
@@ -7524,7 +7521,7 @@ load:   LOAD DATA_SYM
         {
           THD *thd= YYTHD;
           LEX *lex= thd->lex;
-          Lex_input_stream *lip= thd->m_lip;
+          Lex_input_stream *lip= YYLIP;
 
 	  if (lex->sphead)
 	  {
@@ -7566,10 +7563,7 @@ load_data:
         }
         opt_duplicate INTO
         {
-          THD *thd= YYTHD;
-	  LEX *lex= thd->lex;
-          Lex_input_stream *lip= thd->m_lip;
-	  lex->fname_end= lip->ptr;
+	  Lex->fname_end= YYLIP->ptr;
 	}
         TABLE_SYM table_ident
         {
@@ -7787,7 +7781,7 @@ param_marker:
         {
           THD *thd= YYTHD;
 	  LEX *lex= thd->lex;
-          Lex_input_stream *lip= thd->m_lip;
+          Lex_input_stream *lip= YYLIP;
           Item_param *item;
           if (! lex->parsing_options.allows_variable)
           {
@@ -7820,7 +7814,7 @@ literal:
 	| NULL_SYM
           {
             $$ = new Item_null();
-            YYTHD->m_lip->next_state=MY_LEX_OPERATOR_OR_IDENT;
+            YYLIP->next_state= MY_LEX_OPERATOR_OR_IDENT;
           }
 	| FALSE_SYM	{ $$= new Item_int((char*) "FALSE",0,1); }
 	| TRUE_SYM	{ $$= new Item_int((char*) "TRUE",1,1); }
@@ -7924,7 +7918,7 @@ simple_ident:
 	{
           THD *thd= YYTHD;
 	  LEX *lex= thd->lex;
-          Lex_input_stream *lip= thd->m_lip;
+          Lex_input_stream *lip= YYLIP;
 	  sp_variable_t *spv;
           sp_pcontext *spc = lex->spcont;
 	  if (spc && (spv = spc->find_variable(&$1)))
@@ -8537,7 +8531,7 @@ option_type_value:
         {
           THD *thd= YYTHD;
 	  LEX *lex= thd->lex;
-          Lex_input_stream *lip= thd->m_lip;
+          Lex_input_stream *lip= YYLIP;
 
           if (lex->sphead)
           {
@@ -8568,7 +8562,7 @@ option_type_value:
         {
           THD *thd= YYTHD;
 	  LEX *lex= thd->lex;
-          Lex_input_stream *lip= thd->m_lip;
+          Lex_input_stream *lip= YYLIP;
 
           if (lex->sphead)
           {
@@ -9878,7 +9872,7 @@ trigger_tail:
 	{
           THD *thd= YYTHD;
 	  LEX *lex= thd->lex;
-          Lex_input_stream *lip= thd->m_lip;
+          Lex_input_stream *lip= YYLIP;
 	  sp_head *sp;
 	 
 	  if (lex->sphead)
@@ -9971,7 +9965,7 @@ sf_tail:
           { /* $5 */
             THD *thd= YYTHD;
 	    LEX *lex= thd->lex;
-            Lex_input_stream *lip= thd->m_lip;
+            Lex_input_stream *lip= YYLIP;
 	    sp_head *sp;
 
 	    lex->stmt_definition_begin= $1;
@@ -9996,11 +9990,7 @@ sf_tail:
           sp_fdparam_list /* $6 */
           ')' /* $7 */
           { /* $8 */
-            THD *thd= YYTHD;
-	    LEX *lex= thd->lex;
-            Lex_input_stream *lip= thd->m_lip;
-
-	    lex->sphead->m_param_end= lip->tok_start;
+	    Lex->sphead->m_param_end= YYLIP->tok_start;
 	  }
           RETURNS_SYM /* $9 */
 	  { /* $10 */
@@ -10026,7 +10016,7 @@ sf_tail:
           { /* $14 */
             THD *thd= YYTHD;
 	    LEX *lex= thd->lex;
-            Lex_input_stream *lip= thd->m_lip;
+            Lex_input_stream *lip= YYLIP;
 
 	    lex->sphead->m_chistics= &lex->sp_chistics;
 	    lex->sphead->m_body_begin= lip->tok_start;
@@ -10078,18 +10068,14 @@ sp_tail:
 	}
         '('
 	{
-          THD *thd= YYTHD;
-	  LEX *lex= thd->lex;
-          Lex_input_stream *lip= thd->m_lip;
-
-	  lex->sphead->m_param_begin= lip->tok_start+1;
+	  Lex->sphead->m_param_begin= YYLIP->tok_start+1;
 	}
 	sp_pdparam_list
 	')'
 	{
           THD *thd= YYTHD;
 	  LEX *lex= thd->lex;
-          Lex_input_stream *lip= thd->m_lip;
+          Lex_input_stream *lip= YYLIP;
 
 	  lex->sphead->m_param_end= lip->tok_start;
 	  bzero((char *)&lex->sp_chistics, sizeof(st_sp_chistics));
@@ -10098,7 +10084,7 @@ sp_tail:
 	{
           THD *thd= YYTHD;
 	  LEX *lex= thd->lex;
-          Lex_input_stream *lip= thd->m_lip;
+          Lex_input_stream *lip= YYLIP;
 
 	  lex->sphead->m_chistics= &lex->sp_chistics;
 	  lex->sphead->m_body_begin= lip->tok_start;