Remove THD::stmt_backup

sql/sql_class.cc:
  Statement constructor for the case when it's used for backup only
  was removed.
sql/sql_class.h:
  Remove THD::stmt_backup and simplify Statement constructors.
sql/sql_prepare.cc:
  Use an object on stack instead of THD::stmt_backup
sql/sql_select.cc:
  Use an object on stack instead of THD::stmt_backup

1 files changed, 4 insertions, 11 deletions

diff --git a/sql/sql_class.h b/sql/sql_class.h
index fff789d3066..a635a126f84 100644
--- a/sql/sql_class.h
+++ b/sql/sql_class.h
@@ -809,13 +809,11 @@ public:
 
 public:
 
-  /*
-    This constructor is called when statement is a subobject of THD:
-    some variables are initialized in THD::init due to locking problems
-  */
-  Statement();
+  /* This constructor is called for backup statements */
+  Statement() { clear_alloc_root(&main_mem_root); }
 
-  Statement(THD *thd);
+  Statement(enum enum_state state_arg, ulong id_arg,
+            ulong alloc_block_size, ulong prealloc_size);
   virtual ~Statement();
 
   /* Assign execution context (note: not all members) of given stmt to self */
@@ -958,11 +956,6 @@ public:
   /* all prepared statements and cursors of this connection */
   Statement_map stmt_map; 
   /*
-    keeps THD state while it is used for active statement
-    Note: we perform special cleanup for it in THD destructor.
-  */
-  Statement stmt_backup;
-  /*
     A pointer to the stack frame of handle_one_connection(),
     which is called first in the thread for handling a client
   */