bzr commit into mysql-6.0 branch (dlenev:2677) WL#3726

[Dmitry Lenev]

#At file:///home/dlenev/src/bzr/mysql-6.0-3726-w2/

 2677 Dmitry Lenev	2008-06-26
      Fix warnings about passing pointer to not fully-initialized THD
      object to constructor of base Open_tables_state classe, which
      appeared on Windows and were introduced by one of the patches
      implementing WL#3726 "DDL locking for all metadata objects".
modified:
  sql/sql_class.cc
  sql/sql_class.h

per-file messages:
  sql/sql_class.cc
    Moved code preparing Open_tables_state instance for operations
    which open/lock/close tables from class constructor to
    init_open_tables_state() method. This allows us to move such
    initialization of base Open_table_state instance in THD class
    constructor from base classes initialization section to
    constructor's body and thus to get rid of warnings about
    about passing pointer to not fully-initialized THD object
    to base class constructor.
  sql/sql_class.h
    Moved code preparing Open_tables_state instance for operations
    which open/lock/close tables from class constructor to
    init_open_tables_state() method. This allows us to move such
    initialization of base Open_table_state instance in THD class
    constructor from base classes initialization section to
    constructor's body and thus to get rid of warnings about
    about passing pointer to not fully-initialized THD object
    to base class constructor.
=== modified file 'sql/sql_class.cc'
--- a/sql/sql_class.cc	2008-06-11 11:49:58 +0000
+++ b/sql/sql_class.cc	2008-06-26 09:08:27 +0000
@@ -214,12 +214,6 @@ Reprepare_observer::report_error(THD *th
 }
 
 
-Open_tables_state::Open_tables_state(THD *thd, ulong version_arg)
-  :version(version_arg), state_flags(0U)
-{
-  reset_open_tables_state(thd);
-}
-
 /*
   The following functions form part of the C plugin API
 */
@@ -513,7 +507,7 @@ Diagnostics_area::disable_status()
 THD::THD()
    :Statement(&main_lex, &main_mem_root, CONVENTIONAL_EXECUTION,
               /* statement id */ 0),
-   Open_tables_state(this, refresh_version), rli_fake(0),
+   rli_fake(0),
    lock_id(&main_lock_id),
    user_time(0), in_sub_stmt(0),
    binlog_table_maps(0), binlog_flags(0UL),
@@ -615,6 +609,9 @@ THD::THD()
   slave_net = 0;
   command=COM_CONNECT;
   *scramble= '\0';
+
+  /* Call to init() below requires fully initialized Open_tables_state. */
+  init_open_tables_state(this, refresh_version);
 
   init();
   /* Initialize sub structures */

=== modified file 'sql/sql_class.h'
--- a/sql/sql_class.h	2008-06-11 11:49:58 +0000
+++ b/sql/sql_class.h	2008-06-26 09:08:27 +0000
@@ -995,13 +995,22 @@ public:
   MDL_CONTEXT mdl_context;
   MDL_CONTEXT handler_mdl_context;
 
-  /*
-    This constructor serves for creation of Open_tables_state instances
-    which are used as backup storage.
+  /**
+     This constructor initializes Open_tables_state instance which can only
+     be used as backup storage. To prepare Open_tables_state instance for
+     operations which open/lock/close tables (e.g. open_table()) one has to
+     call init_open_tables_state().
   */
   Open_tables_state() : state_flags(0U) { }
 
-  Open_tables_state(THD *thd, ulong version_arg);
+  /**
+     Prepare Open_tables_state instance for operations dealing with tables.
+  */
+  void init_open_tables_state(THD *thd, ulong version_arg)
+  {
+    reset_open_tables_state(thd);
+    version= version_arg;
+  }
 
   void set_open_tables_state(Open_tables_state *state)
   {