Use item->charset() instead of item->str_value.charset()

sql/filesort.cc

@@ -950,7 +950,7 @@ sortlength(SORT_FIELD *sortorder, uint s_length)
 #ifdef USE_STRCOLL
 	if (!sortorder->item->binary())
 	{ 
-	  CHARSET_INFO *cs=sortorder->item->str_value.charset();
+	  CHARSET_INFO *cs=sortorder->item->charset();
 	  if (use_strnxfrm(cs))
 	    sortorder->length= sortorder->length*cs->strxfrm_multiply;
 	}

sql/item_func.cc

@@ -228,11 +228,9 @@ Field *Item_func::tmp_table_field(TABLE *t_arg)
     break;
   case STRING_RESULT:
     if (max_length > 255)
-      res= new Field_blob(max_length, maybe_null, name, t_arg, 
-			  str_value.charset());
+      res= new Field_blob(max_length, maybe_null, name, t_arg, charset());
     else
-      res= new Field_string(max_length, maybe_null, name, t_arg, 
-			    str_value.charset());
+      res= new Field_string(max_length, maybe_null, name, t_arg, charset());
     break;
   }
   return res;

sql/sql_select.cc

@@ -3624,9 +3624,9 @@ Field *create_tmp_field(THD *thd, TABLE *table,Item *item, Item::Type type,
       case STRING_RESULT:
 	if (item_sum->max_length > 255)
 	  return  new Field_blob(item_sum->max_length,maybe_null,
-				 item->name,table,item->str_value.charset());
+				 item->name,table,item->charset());
 	return	new Field_string(item_sum->max_length,maybe_null,
-				 item->name,table,item->str_value.charset());
+				 item->name,table,item->charset());
       }
     }
     thd->fatal_error=1;