diff --git a/mysql-test/r/distinct.result b/mysql-test/r/distinct.result
index 8d7074cd270..e1bbf5adb79 100644
--- a/mysql-test/r/distinct.result
+++ b/mysql-test/r/distinct.result
@@ -1039,4 +1039,14 @@ count(distinct case when id<=63 then id end)
 63
 drop table tb;
 SET @@tmp_table_size= @tmp_table_size_save;
+#
+# MDEV-14695: Assertion `n < m_size' failed in Bounds_checked_array<Element_type>::operator
+#
+CREATE TABLE t1 (b1 BIT, b2 BIT, b3 BIT, b4 BIT , b5 BIT, b6 BIT);
+INSERT INTO t1 VALUES (1,0,0,1,0,1),(0,1,0,0,1,0);
+SELECT DISTINCT b1+'0', b2+'0', b3+'0', b4+'0', b5+'0', b6 +'0'   FROM t1;
+b1+'0'	b2+'0'	b3+'0'	b4+'0'	b5+'0'	b6 +'0'
+1	0	0	1	0	1
+0	1	0	0	1	0
+DROP TABLE t1;
 End of 5.5 tests
diff --git a/mysql-test/t/distinct.test b/mysql-test/t/distinct.test
index 7cf3d6810bb..c11f8b501bc 100644
--- a/mysql-test/t/distinct.test
+++ b/mysql-test/t/distinct.test
@@ -790,4 +790,12 @@ drop table tb;
 
 SET @@tmp_table_size= @tmp_table_size_save;
 
+--echo #
+--echo # MDEV-14695: Assertion `n < m_size' failed in Bounds_checked_array<Element_type>::operator
+--echo #
+
+CREATE TABLE t1 (b1 BIT, b2 BIT, b3 BIT, b4 BIT , b5 BIT, b6 BIT);
+INSERT INTO t1 VALUES (1,0,0,1,0,1),(0,1,0,0,1,0);
+SELECT DISTINCT b1+'0', b2+'0', b3+'0', b4+'0', b5+'0', b6 +'0'   FROM t1;
+DROP TABLE t1;
 --echo End of 5.5 tests
diff --git a/sql/sql_base.cc b/sql/sql_base.cc
index 95ff41cb6f4..4ba74804a05 100644
--- a/sql/sql_base.cc
+++ b/sql/sql_base.cc
@@ -6919,7 +6919,7 @@ static bool setup_natural_join_row_types(THD *thd,
 
 int setup_wild(THD *thd, TABLE_LIST *tables, List<Item> &fields,
 	       List<Item> *sum_func_list,
-	       uint wild_num)
+	       uint wild_num, uint *hidden_bit_fields)
 {
   if (!wild_num)
     return(0);
@@ -6960,7 +6960,7 @@ int setup_wild(THD *thd, TABLE_LIST *tables, List<Item> &fields,
       else if (insert_fields(thd, ((Item_field*) item)->context,
                              ((Item_field*) item)->db_name,
                              ((Item_field*) item)->table_name, &it,
-                             any_privileges))
+                             any_privileges, hidden_bit_fields))
       {
 	if (arena)
 	  thd->restore_active_arena(arena, &backup);
@@ -7425,7 +7425,7 @@ bool get_key_map_from_key_list(key_map *map, TABLE *table,
 bool
 insert_fields(THD *thd, Name_resolution_context *context, const char *db_name,
 	      const char *table_name, List_iterator<Item> *it,
-              bool any_privileges)
+              bool any_privileges, uint *hidden_bit_fields)
 {
   Field_iterator_table_ref field_iterator;
   bool found;
@@ -7545,6 +7545,9 @@ insert_fields(THD *thd, Name_resolution_context *context, const char *db_name,
       else
         it->after(item);   /* Add 'item' to the SELECT list. */
 
+      if (item->type() == Item::FIELD_ITEM && item->field_type() == MYSQL_TYPE_BIT)
+        (*hidden_bit_fields)++;
+
 #ifndef NO_EMBEDDED_ACCESS_CHECKS
       /*
         Set privilege information for the fields of newly created views.
diff --git a/sql/sql_base.h b/sql/sql_base.h
index d6063f1b771..c59a24e4272 100644
--- a/sql/sql_base.h
+++ b/sql/sql_base.h
@@ -154,11 +154,12 @@ bool fill_record_n_invoke_before_triggers(THD *thd, TABLE *table,
                                           enum trg_event_type event);
 bool insert_fields(THD *thd, Name_resolution_context *context,
 		   const char *db_name, const char *table_name,
-                   List_iterator<Item> *it, bool any_privileges);
+                   List_iterator<Item> *it, bool any_privileges,
+                   uint *hidden_bit_fields);
 void make_leaves_list(THD *thd, List<TABLE_LIST> &list, TABLE_LIST *tables,
                       bool full_table_list, TABLE_LIST *boundary);
 int setup_wild(THD *thd, TABLE_LIST *tables, List<Item> &fields,
-	       List<Item> *sum_func_list, uint wild_num);
+	       List<Item> *sum_func_list, uint wild_num, uint * hidden_bit_fields);
 bool setup_fields(THD *thd, Ref_ptr_array ref_pointer_array,
                   List<Item> &item, enum_mark_columns mark_used_columns,
                   List<Item> *sum_func_list, List<Item> *pre_fix,
diff --git a/sql/sql_delete.cc b/sql/sql_delete.cc
index 7b7a7e3f804..48509a46ccb 100644
--- a/sql/sql_delete.cc
+++ b/sql/sql_delete.cc
@@ -760,7 +760,8 @@ l
                                     select_lex->leaf_tables, FALSE, 
                                     DELETE_ACL, SELECT_ACL, TRUE))
     DBUG_RETURN(TRUE);
-  if ((wild_num && setup_wild(thd, table_list, field_list, NULL, wild_num)) ||
+  if ((wild_num && setup_wild(thd, table_list, field_list, NULL, wild_num,
+                              &select_lex->hidden_bit_fields)) ||
       setup_fields(thd, Ref_ptr_array(),
                    field_list, MARK_COLUMNS_READ, NULL, NULL, 0) ||
       setup_conds(thd, table_list, select_lex->leaf_tables, conds) ||
diff --git a/sql/sql_lex.cc b/sql/sql_lex.cc
index 3e36cac96b9..1752689b385 100644
--- a/sql/sql_lex.cc
+++ b/sql/sql_lex.cc
@@ -2126,6 +2126,7 @@ void st_select_lex::init_query()
   select_n_having_items= 0;
   n_sum_items= 0;
   n_child_sum_items= 0;
+  hidden_bit_fields= 0;
   subquery_in_having= explicit_limit= 0;
   is_item_list_lookup= 0;
   first_execution= 1;
@@ -2673,6 +2674,10 @@ ulong st_select_lex::get_table_join_options()
 
 bool st_select_lex::setup_ref_array(THD *thd, uint order_group_num)
 {
+
+  if (!((options & SELECT_DISTINCT) && !group_list.elements))
+    hidden_bit_fields= 0;
+
   // find_order_in_list() may need some extra space, so multiply by two.
   order_group_num*= 2;
 
@@ -2687,7 +2692,8 @@ bool st_select_lex::setup_ref_array(THD *thd, uint order_group_num)
                        select_n_reserved +
                        select_n_having_items +
                        select_n_where_fields +
-                       order_group_num) * 5;
+                       order_group_num +
+                       hidden_bit_fields) * 5;
   if (!ref_pointer_array.is_null())
   {
     /*
diff --git a/sql/sql_lex.h b/sql/sql_lex.h
index 6d281930d1f..68e1885f5e9 100644
--- a/sql/sql_lex.h
+++ b/sql/sql_lex.h
@@ -862,6 +862,11 @@ public:
   uint select_n_where_fields;
   /* reserved for exists 2 in */
   uint select_n_reserved;
+  /*
+   it counts the number of bit fields in the SELECT list. These are used when DISTINCT is
+   converted to a GROUP BY involving BIT fields.
+  */
+  uint hidden_bit_fields;
   enum_parsing_place parsing_place; /* where we are parsing expression */
   enum_parsing_place context_analysis_place; /* where we are in prepare */
   bool with_sum_func;   /* sum function indicator */
diff --git a/sql/sql_select.cc b/sql/sql_select.cc
index 4cd4754596b..1d5abd6a36f 100644
--- a/sql/sql_select.cc
+++ b/sql/sql_select.cc
@@ -799,7 +799,9 @@ JOIN::prepare(TABLE_LIST *tables_init,
       select_lex != select_lex->master_unit()->global_parameters())
     real_og_num+= select_lex->order_list.elements;
 
-  if (setup_wild(thd, tables_list, fields_list, &all_fields, wild_num))
+  DBUG_ASSERT(select_lex->hidden_bit_fields == 0);
+  if (setup_wild(thd, tables_list, fields_list, &all_fields, wild_num,
+                 &select_lex->hidden_bit_fields))
     DBUG_RETURN(-1);
   if (select_lex->setup_ref_array(thd, real_og_num))
     DBUG_RETURN(-1);
diff --git a/sql/sql_union.cc b/sql/sql_union.cc
index 3fe8a24f8bd..3fe90564000 100644
--- a/sql/sql_union.cc
+++ b/sql/sql_union.cc
@@ -1474,6 +1474,7 @@ bool st_select_lex::cleanup()
   }
   inner_refs_list.empty();
   exclude_from_table_unique_test= FALSE;
+  hidden_bit_fields= 0;
   DBUG_RETURN(error);
 }