A cleanup in Item_sum: removing dead code

sql/item_sum.cc

@@ -2679,25 +2679,6 @@ bool Item_sum_and::add()
 ** reset result of a Item_sum with is saved in a tmp_table
 *************************************************************************/
 
-void Item_sum_num::reset_field()
-{
-  double nr= args[0]->val_real();
-  uchar *res=result_field->ptr;
-
-  if (maybe_null)
-  {
-    if (args[0]->null_value)
-    {
-      nr=0.0;
-      result_field->set_null();
-    }
-    else
-      result_field->set_notnull();
-  }
-  float8store(res,nr);
-}
-
-
 void Item_sum_hybrid::reset_field()
 {
   Item *UNINIT_VAR(tmp_item), *arg0;

sql/item_sum.h

@@ -722,24 +722,16 @@ class Aggregator_simple : public Aggregator
 
 class Item_sum_num :public Item_sum
 {
-protected:
-  /*
-   val_xxx() functions may be called several times during the execution of a 
-   query. Derived classes that require extensive calculation in val_xxx()
-   maintain cache of aggregate value. This variable governs the validity of 
-   that cache.
-  */
-  bool is_evaluated;
 public:
-  Item_sum_num(THD *thd): Item_sum(thd), is_evaluated(FALSE) {}
+  Item_sum_num(THD *thd): Item_sum(thd) {}
   Item_sum_num(THD *thd, Item *item_par):
-    Item_sum(thd, item_par), is_evaluated(FALSE) {}
+    Item_sum(thd, item_par) {}
   Item_sum_num(THD *thd, Item *a, Item* b):
-    Item_sum(thd, a, b), is_evaluated(FALSE) {}
+    Item_sum(thd, a, b) {}
   Item_sum_num(THD *thd, List<Item> &list):
-    Item_sum(thd, list), is_evaluated(FALSE) {}
+    Item_sum(thd, list) {}
   Item_sum_num(THD *thd, Item_sum_num *item):
-    Item_sum(thd, item),is_evaluated(item->is_evaluated) {}
+    Item_sum(thd, item) {}
   bool fix_fields(THD *, Item **);
   longlong val_int() { return val_int_from_real();  /* Real as default */ }
   String *val_str(String*str);
@@ -748,7 +740,6 @@ class Item_sum_num :public Item_sum
   {
     return type_handler()->Item_get_date_with_warn(thd, this, ltime, fuzzydate);
   }
-  void reset_field();
 };
 
 
@@ -1705,6 +1696,7 @@ class Item_sum_udf_float :public Item_sum_num
   double val_real() { DBUG_ASSERT(fixed == 1); return 0.0; }
   void clear() {}
   bool add() { return 0; }  
+  void reset_field() { DBUG_ASSERT(0); };
   void update_field() {}
 };
 
@@ -1723,6 +1715,7 @@ class Item_sum_udf_int :public Item_sum_num
   double val_real() { DBUG_ASSERT(fixed == 1); return 0; }
   void clear() {}
   bool add() { return 0; }  
+  void reset_field() { DBUG_ASSERT(0); };
   void update_field() {}
 };
 
@@ -1741,6 +1734,7 @@ class Item_sum_udf_decimal :public Item_sum_num
   my_decimal *val_decimal(my_decimal *) { DBUG_ASSERT(fixed == 1); return 0; }
   void clear() {}
   bool add() { return 0; }
+  void reset_field() { DBUG_ASSERT(0); };
   void update_field() {}
 };
 
@@ -1762,6 +1756,7 @@ class Item_sum_udf_str :public Item_sum_num
   enum Sumfunctype sum_func () const { return UDF_SUM_FUNC; }
   void clear() {}
   bool add() { return 0; }  
+  void reset_field() { DBUG_ASSERT(0); };
   void update_field() {}
 };
 

sql/item_windowfunc.h

@@ -130,6 +130,7 @@ class Item_sum_row_number: public Item_sum_int
     return false;
   }
 
+  void reset_field() { DBUG_ASSERT(0); }
   void update_field() {}
 
   enum Sumfunctype sum_func() const
@@ -193,11 +194,8 @@ class Item_sum_rank: public Item_sum_int
     return cur_rank;
   }
 
+  void reset_field() { DBUG_ASSERT(0); }
   void update_field() {}
-  /*
-   void reset_field();
-    TODO: ^^ what does this do ? It is not called ever?
-  */
 
   enum Sumfunctype sum_func () const
   {
@@ -261,6 +259,7 @@ class Item_sum_dense_rank: public Item_sum_int
     first_add= true;
   }
   bool add();
+  void reset_field() { DBUG_ASSERT(0); }
   void update_field() {}
   longlong val_int()
   {
@@ -460,6 +459,7 @@ class Item_sum_window_with_row_count : public Item_sum_num
 
   void set_row_count(ulonglong count) { partition_row_count_ = count; }
 
+  void reset_field() { DBUG_ASSERT(0); }
  protected:
   longlong get_row_count() { return partition_row_count_; }
  private: