Backport of:

------------------------------------------------------------
revno: 2630.4.39
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w2
timestamp: Thu 2008-06-26 13:08:27 +0400
message:
  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".

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.

sql/sql_class.cc

@@ -202,12 +202,6 @@ bool foreign_key_prefix(Key *a, Key *b)
 ** Thread specific functions
 ****************************************************************************/
 
-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
 */
@@ -440,7 +434,7 @@ bool Drop_table_error_handler::handle_condition(THD *thd,
 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),
    sql_log_bin_toplevel(false),
@@ -542,6 +536,9 @@ THD::THD()
   command=COM_CONNECT;
   *scramble= '\0';
 
+  /* Call to init() below requires fully initialized Open_tables_state. */
+  init_open_tables_state(this, refresh_version);
+
   init();
 #if defined(ENABLED_PROFILING)
   profiling.set_thd(this);

sql/sql_class.h

@@ -984,13 +984,22 @@ 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)
   {