diff --git a/mysql-test/r/sp.result b/mysql-test/r/sp.result
index 4abbb35bd6a..954249a99ce 100644
--- a/mysql-test/r/sp.result
+++ b/mysql-test/r/sp.result
@@ -6061,4 +6061,92 @@ SUM(f2)	bug25373(f1)
 21.300000071526	NULL
 DROP FUNCTION bug25373|
 DROP TABLE t3|
+drop function if exists bug20777|
+drop table if exists examplebug20777|
+create function bug20777(f1 bigint unsigned) returns bigint unsigned
+begin
+set f1 = (f1 - 10); set f1 = (f1 + 10);
+return f1;
+end|
+select bug20777(9223372036854775803) as '9223372036854775803   2**63-5';
+9223372036854775803   2**63-5
+9223372036854775803
+select bug20777(9223372036854775804) as '9223372036854775804   2**63-4';
+9223372036854775804   2**63-4
+9223372036854775804
+select bug20777(9223372036854775805) as '9223372036854775805   2**63-3';
+9223372036854775805   2**63-3
+9223372036854775805
+select bug20777(9223372036854775806) as '9223372036854775806   2**63-2';
+9223372036854775806   2**63-2
+9223372036854775806
+select bug20777(9223372036854775807) as '9223372036854775807   2**63-1';
+9223372036854775807   2**63-1
+9223372036854775807
+select bug20777(9223372036854775808) as '9223372036854775808   2**63+0';
+9223372036854775808   2**63+0
+9223372036854775808
+select bug20777(9223372036854775809) as '9223372036854775809   2**63+1';
+9223372036854775809   2**63+1
+9223372036854775809
+select bug20777(9223372036854775810) as '9223372036854775810   2**63+2';
+9223372036854775810   2**63+2
+9223372036854775810
+select bug20777(-9223372036854775808) as 'lower bounds signed bigint';
+lower bounds signed bigint
+0
+select bug20777(9223372036854775807) as 'upper bounds signed bigint';
+upper bounds signed bigint
+9223372036854775807
+select bug20777(0) as 'lower bounds unsigned bigint';
+lower bounds unsigned bigint
+0
+select bug20777(18446744073709551615) as 'upper bounds unsigned bigint';
+upper bounds unsigned bigint
+18446744073709551615
+select bug20777(18446744073709551616) as 'upper bounds unsigned bigint + 1';
+upper bounds unsigned bigint + 1
+18446744073709551615
+select bug20777(-1) as 'lower bounds unsigned bigint - 1';
+lower bounds unsigned bigint - 1
+0
+select bug20777(1.84e+19) as 'submitter value, 1.84e19';
+submitter value, 1.84e19
+9223372036854775808
+create table examplebug20777 as select 
+0 as 'i',
+bug20777(9223372036854775806) as '2**63-2',
+bug20777(9223372036854775807) as '2**63-1',
+bug20777(9223372036854775808) as '2**63',
+bug20777(9223372036854775809) as '2**63+1',
+bug20777(18446744073709551614) as '2**64-2',
+bug20777(18446744073709551615) as '2**64-1', 
+bug20777(18446744073709551616) as '2**64',
+bug20777(0) as '0',
+bug20777(-1) as '-1';
+insert into examplebug20777 values (1, 9223372036854775806, 9223372036854775807, 223372036854775808, 9223372036854775809, 18446744073709551614, 18446744073709551615, 8446744073709551616, 0, -1);
+show create table examplebug20777;
+Table	Create Table
+examplebug20777	CREATE TABLE `examplebug20777` (
+  `i` int(1) NOT NULL DEFAULT '0',
+  `2**63-2` bigint(20) unsigned DEFAULT NULL,
+  `2**63-1` bigint(20) unsigned DEFAULT NULL,
+  `2**63` bigint(20) unsigned DEFAULT NULL,
+  `2**63+1` bigint(20) unsigned DEFAULT NULL,
+  `2**64-2` bigint(20) unsigned DEFAULT NULL,
+  `2**64-1` bigint(20) unsigned DEFAULT NULL,
+  `2**64` bigint(20) unsigned DEFAULT NULL,
+  `0` bigint(20) unsigned DEFAULT NULL,
+  `-1` bigint(20) unsigned DEFAULT NULL
+) ENGINE=MyISAM DEFAULT CHARSET=latin1
+select * from examplebug20777 order by i;
+i	2**63-2	2**63-1	2**63	2**63+1	2**64-2	2**64-1	2**64	0	-1
+0	9223372036854775806	9223372036854775807	9223372036854775808	9223372036854775809	18446744073709551614	18446744073709551615	18446744073709551615	0	0
+1	9223372036854775806	9223372036854775807	223372036854775808	9223372036854775809	18446744073709551614	18446744073709551615	8446744073709551616	0	0
+drop table examplebug20777;
+select bug20777(18446744073709551613)+1;
+bug20777(18446744073709551613)+1
+18446744073709551614
+drop function bug20777;
+End of 5.0 tests.
 drop table t1,t2;
diff --git a/mysql-test/t/sp.test b/mysql-test/t/sp.test
index d49f36fd6d7..155543fa62e 100644
--- a/mysql-test/t/sp.test
+++ b/mysql-test/t/sp.test
@@ -7018,9 +7018,55 @@ SELECT SUM(f2), bug25373(f1) FROM t3 GROUP BY bug25373(f1) WITH ROLLUP|
 DROP FUNCTION bug25373|
 DROP TABLE t3|
 #
-# NOTE: The delimiter is `|`, and not `;`. It is changed to `;`
-#       at the end of the file!
-#
+# Bug#20777: Function w BIGINT UNSIGNED shows diff. behaviour --ps-protocol
+--disable_warnings
+drop function if exists bug20777|
+drop table if exists examplebug20777|
+--enabled_warnings
+create function bug20777(f1 bigint unsigned) returns bigint unsigned
+begin
+  set f1 = (f1 - 10); set f1 = (f1 + 10);
+return f1;
+end|
+delimiter ;|
+select bug20777(9223372036854775803) as '9223372036854775803   2**63-5';
+select bug20777(9223372036854775804) as '9223372036854775804   2**63-4';
+select bug20777(9223372036854775805) as '9223372036854775805   2**63-3';
+select bug20777(9223372036854775806) as '9223372036854775806   2**63-2';
+select bug20777(9223372036854775807) as '9223372036854775807   2**63-1';
+select bug20777(9223372036854775808) as '9223372036854775808   2**63+0';
+select bug20777(9223372036854775809) as '9223372036854775809   2**63+1';
+select bug20777(9223372036854775810) as '9223372036854775810   2**63+2';
+select bug20777(-9223372036854775808) as 'lower bounds signed bigint';
+select bug20777(9223372036854775807) as 'upper bounds signed bigint';
+select bug20777(0) as 'lower bounds unsigned bigint';
+select bug20777(18446744073709551615) as 'upper bounds unsigned bigint';
+select bug20777(18446744073709551616) as 'upper bounds unsigned bigint + 1';
+select bug20777(-1) as 'lower bounds unsigned bigint - 1';
+select bug20777(1.84e+19) as 'submitter value, 1.84e19';
+
+create table examplebug20777 as select 
+  0 as 'i',
+  bug20777(9223372036854775806) as '2**63-2',
+  bug20777(9223372036854775807) as '2**63-1',
+  bug20777(9223372036854775808) as '2**63',
+  bug20777(9223372036854775809) as '2**63+1',
+  bug20777(18446744073709551614) as '2**64-2',
+  bug20777(18446744073709551615) as '2**64-1', 
+  bug20777(18446744073709551616) as '2**64',
+  bug20777(0) as '0',
+  bug20777(-1) as '-1';
+insert into examplebug20777 values (1, 9223372036854775806, 9223372036854775807, 223372036854775808, 9223372036854775809, 18446744073709551614, 18446744073709551615, 8446744073709551616, 0, -1);
+show create table examplebug20777;
+select * from examplebug20777 order by i;
+
+drop table examplebug20777;
+select bug20777(18446744073709551613)+1;
+drop function bug20777;
+delimiter |;
+
+###
+--echo End of 5.0 tests.
 
 #
 # BUG#NNNN: New bug synopsis
@@ -7029,8 +7075,13 @@ DROP TABLE t3|
 #drop procedure if exists bugNNNN|
 #--enable_warnings
 #create procedure bugNNNN...
-
+#
 # Add bugs above this line. Use existing tables t1 and t2 when
-# practical, or create table t3, t4 etc temporarily (and drop them).
+# practical, or create table t3,t4 etc temporarily (and drop them).
+# NOTE: The delimiter is `|`, and not `;`. It is changed to `;`
+#       at the end of the file!
+#
+
 delimiter ;|
 drop table t1,t2;
+
diff --git a/sql/item_func.cc b/sql/item_func.cc
index b7a708686a8..89a8ecf09b6 100644
--- a/sql/item_func.cc
+++ b/sql/item_func.cc
@@ -4988,10 +4988,8 @@ longlong Item_func_row_count::val_int()
 }
 
 
-Item_func_sp::Item_func_sp(Name_resolution_context *context_arg,
-                           sp_name *name_arg)
-  :Item_func(), context(context_arg), m_name(name_arg), m_sp(NULL),
-   result_field(NULL)
+Item_func_sp::Item_func_sp(Name_resolution_context *context_arg, sp_name *name)
+  :Item_func(), context(context_arg), m_name(name), m_sp(NULL), sp_result_field(NULL)
 {
   maybe_null= 1;
   m_name->init_qname(current_thd);
@@ -5001,9 +4999,8 @@ Item_func_sp::Item_func_sp(Name_resolution_context *context_arg,
 
 
 Item_func_sp::Item_func_sp(Name_resolution_context *context_arg,
-                           sp_name *name_arg, List<Item> &list)
-  :Item_func(list), context(context_arg), m_name(name_arg), m_sp(NULL),
-   result_field(NULL)
+                           sp_name *name, List<Item> &list)
+  :Item_func(list), context(context_arg), m_name(name), m_sp(NULL),sp_result_field(NULL)
 {
   maybe_null= 1;
   m_name->init_qname(current_thd);
@@ -5015,10 +5012,10 @@ Item_func_sp::Item_func_sp(Name_resolution_context *context_arg,
 void
 Item_func_sp::cleanup()
 {
-  if (result_field)
+  if (sp_result_field)
   {
-    delete result_field;
-    result_field= NULL;
+    delete sp_result_field;
+    sp_result_field= NULL;
   }
   m_sp= NULL;
   dummy_table->alias= NULL;
@@ -5047,81 +5044,118 @@ Item_func_sp::func_name() const
 }
 
 
-Field *
-Item_func_sp::sp_result_field(void) const
+
+/**
+  @brief Initialize the result field by creating a temporary dummy table
+    and assign it to a newly created field object. Meta data used to
+    create the field is fetched from the sp_head belonging to the stored
+    proceedure found in the stored procedure functon cache.
+  
+  @note This function should be called from fix_fields to init the result
+    field. It is some what related to Item_field.
+
+  @see Item_field
+
+  @param thd A pointer to the session and thread context.
+
+  @return Function return error status.
+  @retval TRUE is returned on an error
+  @retval FALSE is returned on success.
+*/
+bool
+Item_func_sp::init_result_field(THD *thd)
 {
-  Field *field;
-  DBUG_ENTER("Item_func_sp::sp_result_field");
-  DBUG_PRINT("info", ("sp: %s, flags: %x, level: %lu",
-                      (m_sp ? "YES" : "NO"),
-                      (m_sp ? m_sp->m_flags : (uint)0),
-                      (m_sp ? m_sp->m_recursion_level : (ulong)0)));
+  DBUG_ENTER("Item_func_sp::init_result_field");
 
-  if (!m_sp)
-  {
-    THD *thd= current_thd;
-    if (!(m_sp= sp_find_routine(thd, TYPE_ENUM_FUNCTION, m_name,
-                                &thd->sp_func_cache, TRUE)))
-    {
-      my_error(ER_SP_DOES_NOT_EXIST, MYF(0), "FUNCTION", m_name->m_qname.str);
-      DBUG_RETURN(0);
-    }
-  }
-  if (!dummy_table->alias)
-  {
-    char *empty_name= (char *) "";
-    dummy_table->alias= empty_name;
-    dummy_table->maybe_null= maybe_null;
-    dummy_table->in_use= current_thd;
-    dummy_table->copy_blobs= TRUE;
-    dummy_table->s->table_cache_key.str = empty_name;
-    dummy_table->s->table_name.str= empty_name;
-    dummy_table->s->db.str= empty_name;
-  }
-  if (!(field= m_sp->create_result_field(max_length, name, dummy_table)))
-    my_message(ER_OUT_OF_RESOURCES, ER(ER_OUT_OF_RESOURCES), MYF(0));
+  LEX_STRING empty_name= { STRING_WITH_LEN("") };
+  
+  TABLE_SHARE *share;
 
-  DBUG_RETURN(field);
+  DBUG_ASSERT(m_sp == NULL);
+  DBUG_ASSERT(sp_result_field == NULL);
+
+  if (!(m_sp= sp_find_routine(thd, TYPE_ENUM_FUNCTION, m_name,
+                               &thd->sp_func_cache, TRUE)))
+  {
+    my_error(ER_SP_DOES_NOT_EXIST, MYF(0), "FUNCTION", m_name->m_qname.str);
+    context->process_error(thd);
+    DBUG_RETURN(TRUE);
+  }
+
+  /*
+     A Field need to be attached to a Table.
+     Below we "create" a dummy table by initializing 
+     the needed pointers.
+   */
+  
+  share= dummy_table->s;
+  dummy_table->alias = "";
+  dummy_table->maybe_null = maybe_null;
+  dummy_table->in_use= thd;
+  dummy_table->copy_blobs= TRUE;
+  share->table_cache_key = empty_name;
+  share->table_name = empty_name;
+
+  if (!(sp_result_field= m_sp->create_result_field(max_length, name, dummy_table)))
+  {
+   DBUG_RETURN(TRUE);
+  }
+  
+  if (sp_result_field->pack_length() > sizeof(result_buf))
+  {
+    sp_result_field->move_field(sql_alloc(sp_result_field->pack_length()));
+  } else {
+    sp_result_field->move_field(result_buf);
+  }
+  
+  sp_result_field->null_ptr= (uchar *) &null_value;
+  sp_result_field->null_bit= 1;
+  
+
+  DBUG_RETURN(FALSE);
 }
 
+/**
+  @brief Initialize local members with values from the Field interface.
 
-/*
-  Execute function & store value in field
+  @note called from Item::fix_fields.
+*/
+void Item_func_sp::fix_length_and_dec()
+{
+  DBUG_ENTER("Item_func_sp::fix_length_and_dec");
 
-  RETURN
-   0  value <> NULL
-   1  value =  NULL  or error
+  DBUG_ASSERT(sp_result_field);
+  decimals= sp_result_field->decimals();
+  max_length= sp_result_field->field_length;
+  collation.set(sp_result_field->charset());
+  maybe_null= 1;
+  unsigned_flag= test(sp_result_field->flags & UNSIGNED_FLAG);
+
+  DBUG_VOID_RETURN;
+}
+
+/**
+  @brief Execute function & store value in field.
+
+  @return Function returns error status.
+  @retval FALSE on success.
+  @retval TRUE if an error occurred.
 */
 
 bool
-Item_func_sp::execute(Field **flp)
+Item_func_sp::execute()
 {
   THD *thd= current_thd;
-  Field *f;
-
+  
   /*
     Get field in virtual tmp table to store result. Create the field if
     invoked first time.
   */
-  
-  if (!(f= *flp))
-  {
-    if (!(*flp= f= sp_result_field()))
-    {
-      /* Error set by sp_result_field() */
-      null_value= 1;
-      return TRUE;
-    }
 
-    f->move_field((f->pack_length() > sizeof(result_buf)) ?
-                  sql_alloc(f->pack_length()) : result_buf);
-    f->null_ptr= (uchar *)&null_value;
-    f->null_bit= 1;
-  }
 
   /* Execute function and store the return value in the field. */
 
-  if (execute_impl(thd, f))
+  if (execute_impl(thd))
   {
     null_value= 1;
     context->process_error(thd);
@@ -5130,14 +5164,24 @@ Item_func_sp::execute(Field **flp)
 
   /* Check that the field (the value) is not NULL. */
 
-  null_value= f->is_null();
+  null_value= sp_result_field->is_null();
 
   return null_value;
 }
 
 
+/**
+   @brief Execute function and store the return value in the field.
+
+   @note This function was intended to be the concrete implementation of
+    the interface function execute. This was never realized.
+
+   @return The error state.
+   @retval FALSE on success
+   @retval TRUE if an error occurred.
+*/
 bool
-Item_func_sp::execute_impl(THD *thd, Field *return_value_fld)
+Item_func_sp::execute_impl(THD *thd)
 {
   bool err_status= TRUE;
   Sub_statement_state statement_state;
@@ -5154,7 +5198,7 @@ Item_func_sp::execute_impl(THD *thd, Field *return_value_fld)
     thd->security_ctx= context->security_ctx;
   }
 #endif
-  if (find_and_check_access(thd))
+  if (sp_check_access(thd))
     goto error;
 
   /*
@@ -5175,7 +5219,7 @@ Item_func_sp::execute_impl(THD *thd, Field *return_value_fld)
     function call into binlog.
   */
   thd->reset_sub_statement_state(&statement_state, SUB_STMT_FUNCTION);
-  err_status= m_sp->execute_function(thd, args, arg_count, return_value_fld);
+  err_status= m_sp->execute_function(thd, args, arg_count, sp_result_field); 
   thd->restore_sub_statement_state(&statement_state);
 
 error:
@@ -5190,15 +5234,9 @@ error:
 void
 Item_func_sp::make_field(Send_field *tmp_field)
 {
-  Field *field;
   DBUG_ENTER("Item_func_sp::make_field");
-  if ((field= sp_result_field()))
-  {
-    field->make_field(tmp_field);
-    delete field;
-    DBUG_VOID_RETURN;
-  }
-  init_make_field(tmp_field, MYSQL_TYPE_VARCHAR);  
+  DBUG_ASSERT(sp_result_field);
+  sp_result_field->make_field(tmp_field);
   DBUG_VOID_RETURN;
 }
 
@@ -5206,67 +5244,20 @@ Item_func_sp::make_field(Send_field *tmp_field)
 enum enum_field_types
 Item_func_sp::field_type() const
 {
-  Field *field;
   DBUG_ENTER("Item_func_sp::field_type");
-
-  if (result_field)
-    DBUG_RETURN(result_field->type());
-  if ((field= sp_result_field()))
-  {
-    enum_field_types result= field->type();
-    delete field;
-    DBUG_RETURN(result);
-  }
-  DBUG_RETURN(MYSQL_TYPE_VARCHAR);
+  DBUG_ASSERT(sp_result_field);
+  DBUG_RETURN(sp_result_field->type());
 }
 
-
 Item_result
 Item_func_sp::result_type() const
 {
-  Field *field;
   DBUG_ENTER("Item_func_sp::result_type");
-  DBUG_PRINT("info", ("m_sp: 0x%lx", (long) m_sp));
-
-  if (result_field)
-    DBUG_RETURN(result_field->result_type());
-  if ((field= sp_result_field()))
-  {
-    Item_result result= field->result_type();
-    delete field;
-    DBUG_RETURN(result);
-  }
-  DBUG_RETURN(STRING_RESULT);
+  DBUG_PRINT("info", ("m_sp = %p", m_sp));
+  DBUG_ASSERT(sp_result_field);
+  DBUG_RETURN(sp_result_field->result_type());
 }
 
-void
-Item_func_sp::fix_length_and_dec()
-{
-  Field *field;
-  DBUG_ENTER("Item_func_sp::fix_length_and_dec");
-
-  if (result_field)
-  {
-    decimals= result_field->decimals();
-    max_length= result_field->field_length;
-    collation.set(result_field->charset());
-    DBUG_VOID_RETURN;
-  }
-
-  if (!(field= sp_result_field()))
-  {
-    context->process_error(current_thd);
-    DBUG_VOID_RETURN;
-  }
-  decimals= field->decimals();
-  max_length= field->field_length;
-  collation.set(field->charset());
-  maybe_null= 1;
-  delete field;
-  DBUG_VOID_RETURN;
-}
-
-
 longlong Item_func_found_rows::val_int()
 {
   DBUG_ASSERT(fixed == 1);
@@ -5277,57 +5268,39 @@ longlong Item_func_found_rows::val_int()
 Field *
 Item_func_sp::tmp_table_field(TABLE *t_arg)
 {
-  Field *field= 0;
   DBUG_ENTER("Item_func_sp::tmp_table_field");
 
-  if (m_sp)
-    field= m_sp->create_result_field(max_length, (const char*) name, t_arg);
-  
-  if (!field) 
-    field= Item_func::tmp_table_field(t_arg);
-
-  if (!field)
-    my_message(ER_OUT_OF_RESOURCES, ER(ER_OUT_OF_RESOURCES), MYF(0));
-
-  DBUG_RETURN(field);
+  DBUG_ASSERT(sp_result_field);
+  DBUG_RETURN(sp_result_field);
 }
 
 
-/*
-  Find the function and check access rights to the function
-
-  SYNOPSIS
-    find_and_check_access()
-    thd           thread handler
-
-  RETURN
-    FALSE    Access granted
-    TRUE     Requested access can't be granted or function doesn't exists
-
-  NOTES
-    Checks if requested access to function can be granted to user.
+/**
+  @brief Checks if requested access to function can be granted to user.
     If function isn't found yet, it searches function first.
     If function can't be found or user don't have requested access
     error is raised.
+
+  @param thd thread handler
+
+  @return Indication if the access was granted or not.
+  @retval FALSE Access is granted.
+  @retval TRUE Requested access can't be granted or function doesn't exists.
+    
 */
 
 bool
-Item_func_sp::find_and_check_access(THD *thd)
+Item_func_sp::sp_check_access(THD *thd)
 {
-  if (! m_sp && ! (m_sp= sp_find_routine(thd, TYPE_ENUM_FUNCTION, m_name,
-                                         &thd->sp_func_cache, TRUE)))
-  {
-    my_error(ER_SP_DOES_NOT_EXIST, MYF(0), "FUNCTION", m_name->m_qname.str);
-    return TRUE;
-  }
-
+  DBUG_ENTER("Item_func_sp::sp_check_access");
+  DBUG_ASSERT(m_sp);
 #ifndef NO_EMBEDDED_ACCESS_CHECKS
   if (check_routine_access(thd, EXECUTE_ACL,
 			   m_sp->m_db.str, m_sp->m_name.str, 0, FALSE))
-    return TRUE;
+    DBUG_RETURN(TRUE);
 #endif
 
-  return FALSE;
+  DBUG_RETURN(FALSE);
 }
 
 
@@ -5335,9 +5308,25 @@ bool
 Item_func_sp::fix_fields(THD *thd, Item **ref)
 {
   bool res;
+  DBUG_ENTER("Item_func_sp::fix_fields");
   DBUG_ASSERT(fixed == 0);
+ 
+  /*
+    We must call init_result_field before Item_func::fix_fields() 
+    to make m_sp and result_field members available to fix_length_and_dec(),
+    which is called from Item_func::fix_fields().
+  */
+  res= init_result_field(thd);
+
+  if (res)
+    DBUG_RETURN(res);
+
   res= Item_func::fix_fields(thd, ref);
-  if (!res && thd->lex->view_prepare_mode)
+
+  if (res)
+    DBUG_RETURN(res);
+
+  if (thd->lex->view_prepare_mode)
   {
     /*
       Here we check privileges of the stored routine only during view
@@ -5349,15 +5338,17 @@ Item_func_sp::fix_fields(THD *thd, Item **ref)
       good idea especially if the view has SQL SECURITY DEFINER and
       the used stored procedure has SQL SECURITY DEFINER.
     */
-    res= find_and_check_access(thd);
+    res= sp_check_access(thd);
 #ifndef NO_EMBEDDED_ACCESS_CHECKS
+    /*
+      Try to set and restore the security context to see whether it's valid
+    */
     Security_context *save_secutiry_ctx;
-    if (!res && !(res= set_routine_security_ctx(thd, m_sp, false,
-                                                &save_secutiry_ctx)))
-    {
+    res= set_routine_security_ctx(thd, m_sp, false, &save_secutiry_ctx);
+    if (!res)
       sp_restore_security_context(thd, save_secutiry_ctx);
-    }
+    
 #endif /* ! NO_EMBEDDED_ACCESS_CHECKS */
   }
-  return res;
+  DBUG_RETURN(res);
 }
diff --git a/sql/item_func.h b/sql/item_func.h
index 3306b059097..90320c9bc56 100644
--- a/sql/item_func.h
+++ b/sql/item_func.h
@@ -1434,12 +1434,15 @@ private:
   sp_name *m_name;
   mutable sp_head *m_sp;
   TABLE *dummy_table;
-  Field *result_field;
   char result_buf[64];
+  /*
+     The result field of the concrete stored function.
+  */
+  Field *sp_result_field;
 
-  bool execute(Field **flp);
-  bool execute_impl(THD *thd, Field *return_value_fld);
-  Field *sp_result_field(void) const;
+  bool execute();
+  bool execute_impl(THD *thd);
+  bool init_result_field(THD *thd);
 
 public:
 
@@ -1465,23 +1468,23 @@ public:
 
   longlong val_int()
   {
-    if (execute(&result_field))
+    if (execute())
       return (longlong) 0;
-    return result_field->val_int();
+    return sp_result_field->val_int();
   }
 
   double val_real()
   {
-    if (execute(&result_field))
+    if (execute())
       return 0.0;
-    return result_field->val_real();
+    return sp_result_field->val_real();
   }
 
   my_decimal *val_decimal(my_decimal *dec_buf)
   {
-    if (execute(&result_field))
+    if (execute())
       return NULL;
-    return result_field->val_decimal(dec_buf);
+    return sp_result_field->val_decimal(dec_buf);
   }
 
   String *val_str(String *str)
@@ -1490,7 +1493,7 @@ public:
     char buff[20];
     buf.set(buff, 20, str->charset());
     buf.length(0);
-    if (execute(&result_field))
+    if (execute())
       return NULL;
     /*
       result_field will set buf pointing to internal buffer
@@ -1498,7 +1501,7 @@ public:
       when SP is executed. In order to prevent occasional
       corruption of returned value, we make here a copy.
     */
-    result_field->val_str(&buf);
+    sp_result_field->val_str(&buf);
     str->copy(buf);
     return str;
   }
@@ -1506,11 +1509,11 @@ public:
   virtual bool change_context_processor(byte *cntx)
     { context= (Name_resolution_context *)cntx; return FALSE; }
 
-  void fix_length_and_dec();
-  bool find_and_check_access(THD * thd);
+  bool sp_check_access(THD * thd);
   virtual enum Functype functype() const { return FUNC_SP; }
 
   bool fix_fields(THD *thd, Item **ref);
+  void fix_length_and_dec(void);
   bool is_expensive() { return 1; }
 };