Remove has_error as a member from Item_sum and use THD::is_error() instead

Additionally, allow a query with window functions to be killed by the user during
its execution.

sql/item_sum.cc

@@ -441,7 +441,6 @@ Item_sum::Item_sum(THD *thd, List<Item> &list): Item_func_or_sum(thd, list)
   mark_as_sum_func();
   init_aggregator();
   list.empty();					// Fields are used
-  has_error= FALSE;
 }
 
 
@@ -453,7 +452,7 @@ Item_sum::Item_sum(THD *thd, Item_sum *item):
   Item_func_or_sum(thd, item),
   aggr_sel(item->aggr_sel),
   nest_level(item->nest_level), aggr_level(item->aggr_level),
-  quick_group(item->quick_group), has_error(FALSE),
+  quick_group(item->quick_group),
   orig_args(NULL)
 {
   if (arg_count <= 2)

sql/item_sum.h

@@ -367,7 +367,6 @@ class Item_sum :public Item_func_or_sum
   int8 max_arg_level;     /* max level of unbound column references          */
   int8 max_sum_func_level;/* max level of aggregation for embedded functions */
   bool quick_group;			/* If incremental update of fields */
-  bool has_error;
   /*
     This list is used by the check for mixing non aggregated fields and
     sum functions in the ONLY_FULL_GROUP_BY_MODE. We save all outer fields
@@ -389,19 +388,19 @@ class Item_sum :public Item_func_or_sum
 public:  
 
   void mark_as_sum_func();
-  Item_sum(THD *thd): Item_func_or_sum(thd), quick_group(1), has_error(0)
+  Item_sum(THD *thd): Item_func_or_sum(thd), quick_group(1)
   {
     mark_as_sum_func();
     init_aggregator();
   }
   Item_sum(THD *thd, Item *a): Item_func_or_sum(thd, a), quick_group(1),
-    has_error(0), orig_args(tmp_orig_args)
+    orig_args(tmp_orig_args)
   {
     mark_as_sum_func();
     init_aggregator();
   }
   Item_sum(THD *thd, Item *a, Item *b): Item_func_or_sum(thd, a, b),
-    quick_group(1), has_error(0), orig_args(tmp_orig_args)
+    quick_group(1), orig_args(tmp_orig_args)
   {
     mark_as_sum_func();
     init_aggregator();

sql/item_windowfunc.h

@@ -767,7 +767,6 @@ class Item_sum_percentile_disc : public Item_sum_cume_dist,
       if (prev_value >1 || prev_value < 0)
       {
         my_error(ER_ARGUMENT_OUT_OF_RANGE, MYF(0));
-        has_error= TRUE;
         return true;
       }
       first_call= false;
@@ -778,7 +777,6 @@ class Item_sum_percentile_disc : public Item_sum_cume_dist,
     if (prev_value !=  arg_val)
     {
       my_error(ER_ARGUMENT_NOT_CONSTANT, MYF(0));
-      has_error= TRUE;
       return true;
     }
 
@@ -805,7 +803,6 @@ class Item_sum_percentile_disc : public Item_sum_cume_dist,
 
   void clear()
   {
-    has_error= false;
     val_calculated= false;
     first_call= true;
     value->clear();
@@ -890,7 +887,6 @@ class Item_sum_percentile_cont : public Item_sum_cume_dist,
       if (prev_value >1 || prev_value < 0)
       {
         my_error(ER_ARGUMENT_OUT_OF_RANGE, MYF(0));
-        has_error= TRUE;
         return true;
       }
     }
@@ -899,7 +895,6 @@ class Item_sum_percentile_cont : public Item_sum_cume_dist,
     if (prev_value !=  arg_val)
     {
       my_error(ER_ARGUMENT_NOT_CONSTANT, MYF(0));
-      has_error= TRUE;
       return true;
     }
 
@@ -937,7 +932,6 @@ class Item_sum_percentile_cont : public Item_sum_cume_dist,
   void clear()
   {
     first_call= true;
-    has_error= false;
     floor_value->clear();
     ceil_value->clear();
     floor_val_calculated= false;

sql/sql_window.cc

@@ -1080,8 +1080,6 @@ class Frame_cursor : public Sql_alloc
     while ((item_sum= it++))
     {
       item_sum->add();
-      if (item_sum->has_error)
-        return;
     }
   }
 
@@ -2807,10 +2805,11 @@ bool compute_window_func(THD *thd,
         cursor_manager->notify_cursors_next_row();
       }
 
-      /* check if we found any error in the window function while calling the add function */
+      /* Check if we found any error in the window function while adding values
+         through cursors. */
+      if (thd->is_error() || thd->is_killed())
+        break;
 
-      if (win_func->window_func()->has_error)
-        goto label;
 
       /* Return to current row after notifying cursors for each window
          function. */
@@ -2824,7 +2823,6 @@ bool compute_window_func(THD *thd,
     rownum++;
   }
 
-label:
   my_free(rowid_buf);
   partition_trackers.delete_elements();
   end_read_record(&info);