MDEV-17556 Assertion `bitmap_is_set_all(&table->s->all_set)' failed

The assertion failed in handler::ha_reset upon SELECT under
READ UNCOMMITTED from table with index on virtual column.

This was the debug-only failure, though the problem is mush wider:
* MY_BITMAP is a structure containing my_bitmap_map, the latter is a raw
 bitmap.
* read_set, write_set and vcol_set of TABLE are the pointers to MY_BITMAP
* The rest of MY_BITMAPs are stored in TABLE and TABLE_SHARE
* The pointers to the stored MY_BITMAPs, like orig_read_set etc, and
 sometimes all_set and tmp_set, are assigned to the pointers.
* Sometimes tmp_use_all_columns is used to substitute the raw bitmap
 directly with all_set.bitmap
* Sometimes even bitmaps are directly modified, like in
TABLE::update_virtual_field(): bitmap_clear_all(&tmp_set) is called.

The last three bullets in the list, when used together (which is mostly
always) make the program flow cumbersome and impossible to follow,
notwithstanding the errors they cause, like this MDEV-17556, where tmp_set
pointer was assigned to read_set, write_set and vcol_set, then its bitmap
was substituted with all_set.bitmap by dbug_tmp_use_all_columns() call,
and then bitmap_clear_all(&tmp_set) was applied to all this.

To untangle this knot, the rule should be applied:
* Never substitute bitmaps! This patch is about this.
 orig_*, all_set bitmaps are never substituted already.

This patch changes the following function prototypes:
* tmp_use_all_columns, dbug_tmp_use_all_columns
 to accept MY_BITMAP** and to return MY_BITMAP * instead of my_bitmap_map*
* tmp_restore_column_map, dbug_tmp_restore_column_maps to accept
 MY_BITMAP* instead of my_bitmap_map*

These functions now will substitute read_set/write_set/vcol_set directly,
and won't touch underlying bitmaps.

Author: FooBarrior

plugin/feedback/sender_thread.cc

@@ -47,7 +47,7 @@ static int table_to_string(TABLE *table, String *result)
 
   res= table->file->ha_rnd_init(1);
 
-  dbug_tmp_use_all_columns(table, table->read_set);
+  dbug_tmp_use_all_columns(table, &table->read_set);
 
   while(!res && !table->file->ha_rnd_next(table->record[0]))
   {

sql/field.cc

@@ -7976,11 +7976,10 @@ uint Field_varstring::get_key_image(uchar *buff, uint length,
 {
   String val;
   uint local_char_length;
-  my_bitmap_map *old_map;
 
-  old_map= dbug_tmp_use_all_columns(table, table->read_set);
+  MY_BITMAP *old_map= dbug_tmp_use_all_columns(table, &table->read_set);
   val_str(&val, &val);
-  dbug_tmp_restore_column_map(table->read_set, old_map);
+  dbug_tmp_restore_column_map(&table->read_set, old_map);
 
   local_char_length= val.charpos(length / field_charset->mbmaxlen);
   if (local_char_length < val.length())
@@ -11496,7 +11495,7 @@ key_map Field::get_possible_keys()
 
 bool Field::validate_value_in_record_with_warn(THD *thd, const uchar *record)
 {
-  my_bitmap_map *old_map= dbug_tmp_use_all_columns(table, table->read_set);
+    MY_BITMAP *old_map= dbug_tmp_use_all_columns(table, &table->read_set);
   bool rc;
   if ((rc= validate_value_in_record(thd, record)))
   {
@@ -11508,7 +11507,7 @@ bool Field::validate_value_in_record_with_warn(THD *thd, const uchar *record)
                         ER_THD(thd, ER_INVALID_DEFAULT_VALUE_FOR_FIELD),
                         ErrConvString(&tmp).ptr(), field_name.str);
   }
-  dbug_tmp_restore_column_map(table->read_set, old_map);
+  dbug_tmp_restore_column_map(&table->read_set, old_map);
   return rc;
 }
 

sql/ha_partition.cc

@@ -4278,7 +4278,7 @@ int ha_partition::write_row(uchar * buf)
   int error;
   longlong func_value;
   bool have_auto_increment= table->next_number_field && buf == table->record[0];
-  my_bitmap_map *old_map;
+  MY_BITMAP *old_map;
   THD *thd= ha_thd();
   sql_mode_t saved_sql_mode= thd->variables.sql_mode;
   bool saved_auto_inc_field_not_null= table->auto_increment_field_not_null;
@@ -4320,9 +4320,9 @@ int ha_partition::write_row(uchar * buf)
     }
   }
 
-  old_map= dbug_tmp_use_all_columns(table, table->read_set);
+  old_map= dbug_tmp_use_all_columns(table, &table->read_set);
   error= m_part_info->get_partition_id(m_part_info, &part_id, &func_value);
-  dbug_tmp_restore_column_map(table->read_set, old_map);
+  dbug_tmp_restore_column_map(&table->read_set, old_map);
   if (unlikely(error))
   {
     m_part_info->err_value= func_value;
@@ -11191,13 +11191,12 @@ int ha_partition::bulk_update_row(const uchar *old_data, const uchar *new_data,
   int error= 0;
   uint32 part_id;
   longlong func_value;
-  my_bitmap_map *old_map;
   DBUG_ENTER("ha_partition::bulk_update_row");
 
-  old_map= dbug_tmp_use_all_columns(table, table->read_set);
+  MY_BITMAP *old_map= dbug_tmp_use_all_columns(table, &table->read_set);
   error= m_part_info->get_partition_id(m_part_info, &part_id,
                                        &func_value);
-  dbug_tmp_restore_column_map(table->read_set, old_map);
+  dbug_tmp_restore_column_map(&table->read_set, old_map);
   if (unlikely(error))
   {
     m_part_info->err_value= func_value;

sql/item.cc

@@ -1624,9 +1624,9 @@ int Item::save_in_field_no_warnings(Field *field, bool no_conversions)
   Sql_mode_save sql_mode(thd);
   thd->variables.sql_mode&= ~(MODE_NO_ZERO_IN_DATE | MODE_NO_ZERO_DATE);
   thd->variables.sql_mode|= MODE_INVALID_DATES;
-  my_bitmap_map *old_map= dbug_tmp_use_all_columns(table, table->write_set);
+  MY_BITMAP *old_map= dbug_tmp_use_all_columns(table, &table->write_set);
   res= save_in_field(field, no_conversions);
-  dbug_tmp_restore_column_map(table->write_set, old_map);
+  dbug_tmp_restore_column_map(&table->write_set, old_map);
   return res;
 }
 
@@ -6051,7 +6051,7 @@ bool Item_field::fix_fields(THD *thd, Item **reference)
   Field *from_field= (Field *)not_found_field;
   bool outer_fixed= false;
   SELECT_LEX *select= thd->lex->current_select;
-  
+
   if (select && select->in_tvc)
   {
     my_error(ER_FIELD_REFERENCE_IN_TVC, MYF(0), full_name());
@@ -6947,7 +6947,7 @@ Item *Item_string::make_odbc_literal(THD *thd, const LEX_CSTRING *typestr)
 }
 
 
-static int save_int_value_in_field (Field *field, longlong nr, 
+static int save_int_value_in_field (Field *field, longlong nr,
                                     bool null_value, bool unsigned_flag)
 {
   if (null_value)

sql/item_cmpfunc.cc

@@ -345,13 +345,13 @@ static bool convert_const_to_int(THD *thd, Item_field *field_item,
     TABLE *table= field->table;
     Sql_mode_save sql_mode(thd);
     Check_level_instant_set check_level_save(thd, CHECK_FIELD_IGNORE);
-    my_bitmap_map *old_maps[2] = { NULL, NULL };
+    MY_BITMAP *old_maps[2] = { NULL, NULL };
     ulonglong UNINIT_VAR(orig_field_val); /* original field value if valid */
 
     /* table->read_set may not be set if we come here from a CREATE TABLE */
     if (table && table->read_set)
       dbug_tmp_use_all_columns(table, old_maps,
-                               table->read_set, table->write_set);
+                               &table->read_set, &table->write_set);
     /* For comparison purposes allow invalid dates like 2000-01-32 */
     thd->variables.sql_mode= (thd->variables.sql_mode & ~MODE_NO_ZERO_DATE) |
                              MODE_INVALID_DATES;
@@ -392,7 +392,7 @@ static bool convert_const_to_int(THD *thd, Item_field *field_item,
       DBUG_ASSERT(!result);
     }
     if (table && table->read_set)
-      dbug_tmp_restore_column_maps(table->read_set, table->write_set, old_maps);
+      dbug_tmp_restore_column_maps(&table->read_set, &table->write_set, old_maps);
   }
   return result;
 }
@@ -3101,7 +3101,7 @@ bool Item_func_decode_oracle::fix_length_and_dec()
 /*
   Aggregate all THEN and ELSE expression types
   and collations when string result
-  
+
   @param THD       - current thd
   @param start     - an element in args to start aggregating from
 */

sql/key.cc

@@ -244,14 +244,13 @@ void key_restore(uchar *to_record, const uchar *from_key, KEY *key_info,
     else if (key_part->key_part_flag & HA_VAR_LENGTH_PART)
     {
       Field *field= key_part->field;
-      my_bitmap_map *old_map;
       my_ptrdiff_t ptrdiff= to_record - field->table->record[0];
       field->move_field_offset(ptrdiff);
       key_length-= HA_KEY_BLOB_LENGTH;
       length= MY_MIN(key_length, key_part->length);
-      old_map= dbug_tmp_use_all_columns(field->table, field->table->write_set);
+      MY_BITMAP *old_map= dbug_tmp_use_all_columns(field->table, &field->table->write_set);
       field->set_key_image(from_key, length);
-      dbug_tmp_restore_column_map(field->table->write_set, old_map);
+      dbug_tmp_restore_column_map(&field->table->write_set, old_map);
       from_key+= HA_KEY_BLOB_LENGTH;
       field->move_field_offset(-ptrdiff);
     }
@@ -419,7 +418,7 @@ void field_unpack(String *to, Field *field, const uchar *rec, uint max_length,
 
 void key_unpack(String *to, TABLE *table, KEY *key)
 {
-  my_bitmap_map *old_map= dbug_tmp_use_all_columns(table, table->read_set);
+  MY_BITMAP *old_map= dbug_tmp_use_all_columns(table, &table->read_set);
   DBUG_ENTER("key_unpack");
 
   to->length(0);
@@ -443,7 +442,7 @@ void key_unpack(String *to, TABLE *table, KEY *key)
     field_unpack(to, key_part->field, table->record[0], key_part->length,
                  MY_TEST(key_part->key_part_flag & HA_PART_KEY_SEG));
  }
-  dbug_tmp_restore_column_map(table->read_set, old_map);
+  dbug_tmp_restore_column_map(&table->read_set, old_map);
   DBUG_VOID_RETURN;
 }
 

sql/log_event.cc

@@ -13699,11 +13699,11 @@ int Rows_log_event::update_sequence()
     /* This event come from a setval function executed on the master.
        Update the sequence next_number and round, like we do with setval()
     */
-    my_bitmap_map *old_map= dbug_tmp_use_all_columns(table,
-                                                     table->read_set);
+    MY_BITMAP *old_map= dbug_tmp_use_all_columns(table,
+                                                 &table->read_set);
     longlong nextval= table->field[NEXT_FIELD_NO]->val_int();
     longlong round= table->field[ROUND_FIELD_NO]->val_int();
-    dbug_tmp_restore_column_map(table->read_set, old_map);
+    dbug_tmp_restore_column_map(&table->read_set, old_map);
 
     return table->s->sequence->set_value(table, nextval, round, 0) > 0;
   }

sql/opt_range.cc

@@ -3264,8 +3264,7 @@ bool calculate_cond_selectivity_for_table(THD *thd, TABLE *table, Item **cond)
 
 void store_key_image_to_rec(Field *field, uchar *ptr, uint len)
 {
-  /* Do the same as print_key() does */ 
-  my_bitmap_map *old_map;
+  /* Do the same as print_key() does */
 
   if (field->real_maybe_null())
   {
@@ -3277,10 +3276,10 @@ void store_key_image_to_rec(Field *field, uchar *ptr, uint len)
     field->set_notnull();
     ptr++;
   }    
-  old_map= dbug_tmp_use_all_columns(field->table,
-                                    field->table->write_set);
+  MY_BITMAP *old_map= dbug_tmp_use_all_columns(field->table,
+                                    &field->table->write_set);
   field->set_key_image(ptr, len); 
-  dbug_tmp_restore_column_map(field->table->write_set, old_map);
+  dbug_tmp_restore_column_map(&field->table->write_set, old_map);
 }
 
 #ifdef WITH_PARTITION_STORAGE_ENGINE
@@ -3495,7 +3494,7 @@ bool prune_partitions(THD *thd, TABLE *table, Item *pprune_cond)
   PART_PRUNE_PARAM prune_param;
   MEM_ROOT alloc;
   RANGE_OPT_PARAM  *range_par= &prune_param.range_param;
-  my_bitmap_map *old_sets[2];
+  MY_BITMAP *old_sets[2];
 
   prune_param.part_info= part_info;
   init_sql_alloc(&alloc, "prune_partitions",
@@ -3512,7 +3511,7 @@ bool prune_partitions(THD *thd, TABLE *table, Item *pprune_cond)
   }
 
   dbug_tmp_use_all_columns(table, old_sets, 
-                           table->read_set, table->write_set);
+                           &table->read_set, &table->write_set);
   range_par->thd= thd;
   range_par->table= table;
   /* range_par->cond doesn't need initialization */
@@ -3609,7 +3608,7 @@ bool prune_partitions(THD *thd, TABLE *table, Item *pprune_cond)
   retval= FALSE; // some partitions are used
   mark_all_partitions_as_used(prune_param.part_info);
 end:
-  dbug_tmp_restore_column_maps(table->read_set, table->write_set, old_sets);
+  dbug_tmp_restore_column_maps(&table->read_set, &table->write_set, old_sets);
   thd->no_errors=0;
   thd->mem_root= range_par->old_root;
   free_root(&alloc,MYF(0));			// Return memory & allocator
@@ -14852,8 +14851,8 @@ static void
 print_sel_arg_key(Field *field, const uchar *key, String *out)
 {
   TABLE *table= field->table;
-  my_bitmap_map *old_sets[2];
-  dbug_tmp_use_all_columns(table, old_sets, table->read_set, table->write_set);
+  MY_BITMAP *old_sets[2];
+  dbug_tmp_use_all_columns(table, old_sets, &table->read_set, &table->write_set);
 
   if (field->real_maybe_null())
   {
@@ -14873,7 +14872,7 @@ print_sel_arg_key(Field *field, const uchar *key, String *out)
     field->val_str(out);
 
 end:
-  dbug_tmp_restore_column_maps(table->read_set, table->write_set, old_sets);
+  dbug_tmp_restore_column_maps(&table->read_set, &table->write_set, old_sets);
 }
 
 
@@ -14968,9 +14967,9 @@ print_key(KEY_PART *key_part, const uchar *key, uint used_length)
   const uchar *key_end= key+used_length;
   uint store_length;
   TABLE *table= key_part->field->table;
-  my_bitmap_map *old_sets[2];
+  MY_BITMAP *old_sets[2];
 
-  dbug_tmp_use_all_columns(table, old_sets, table->read_set, table->write_set);
+  dbug_tmp_use_all_columns(table, old_sets, &table->read_set, &table->write_set);
 
   for (; key < key_end; key+=store_length, key_part++)
   {
@@ -14997,24 +14996,24 @@ print_key(KEY_PART *key_part, const uchar *key, uint used_length)
     if (key+store_length < key_end)
       fputc('/',DBUG_FILE);
   }
-  dbug_tmp_restore_column_maps(table->read_set, table->write_set, old_sets);
+  dbug_tmp_restore_column_maps(&table->read_set, &table->write_set, old_sets);
 }
 
 
 static void print_quick(QUICK_SELECT_I *quick, const key_map *needed_reg)
 {
   char buf[MAX_KEY/8+1];
   TABLE *table;
-  my_bitmap_map *old_sets[2];
+  MY_BITMAP *old_sets[2];
   DBUG_ENTER("print_quick");
   if (!quick)
     DBUG_VOID_RETURN;
   DBUG_LOCK_FILE;
 
   table= quick->head;
-  dbug_tmp_use_all_columns(table, old_sets, table->read_set, table->write_set);
+  dbug_tmp_use_all_columns(table, old_sets, &table->read_set, &table->write_set);
   quick->dbug_dump(0, TRUE);
-  dbug_tmp_restore_column_maps(table->read_set, table->write_set, old_sets);
+  dbug_tmp_restore_column_maps(&table->read_set, &table->write_set, old_sets);
 
   fprintf(DBUG_FILE,"other_keys: 0x%s:\n", needed_reg->print(buf));
 

sql/partition_info.cc

@@ -1449,13 +1449,13 @@ void partition_info::print_no_partition_found(TABLE *table_arg, myf errflag)
       buf_ptr= (char*)"from column_list";
     else
     {
-      my_bitmap_map *old_map= dbug_tmp_use_all_columns(table_arg, table_arg->read_set);
+      MY_BITMAP *old_map= dbug_tmp_use_all_columns(table_arg, &table_arg->read_set);
       if (part_expr->null_value)
         buf_ptr= (char*)"NULL";
       else
         longlong10_to_str(err_value, buf,
                      part_expr->unsigned_flag ? 10 : -10);
-      dbug_tmp_restore_column_map(table_arg->read_set, old_map);
+      dbug_tmp_restore_column_map(&table_arg->read_set, old_map);
     }
     my_error(ER_NO_PARTITION_FOR_GIVEN_VALUE, errflag, buf_ptr);
   }

sql/protocol.cc

@@ -1251,15 +1251,15 @@ bool Protocol_text::store(Field *field)
   CHARSET_INFO *tocs= this->thd->variables.character_set_results;
 #ifdef DBUG_ASSERT_EXISTS
   TABLE *table= field->table;
-  my_bitmap_map *old_map= 0;
+  MY_BITMAP *old_map= 0;
   if (table->file)
-    old_map= dbug_tmp_use_all_columns(table, table->read_set);
+    old_map= dbug_tmp_use_all_columns(table, &table->read_set);
 #endif
 
   field->val_str(&str);
 #ifdef DBUG_ASSERT_EXISTS
   if (old_map)
-    dbug_tmp_restore_column_map(table->read_set, old_map);
+    dbug_tmp_restore_column_map(&table->read_set, old_map);
 #endif
 
   return store_string_aux(str.ptr(), str.length(), str.charset(), tocs);

sql/sql_handler.cc

@@ -689,7 +689,6 @@ mysql_ha_fix_cond_and_key(SQL_HANDLER *handler,
 
       for (keypart_map= key_len=0 ; (item=it_ke++) ; key_part++)
       {
-        my_bitmap_map *old_map;
 	/* note that 'item' can be changed by fix_fields() call */
         if (item->fix_fields_if_needed_for_scalar(thd, it_ke.ref()))
           return 1;
@@ -701,9 +700,9 @@ mysql_ha_fix_cond_and_key(SQL_HANDLER *handler,
         }
         if (!in_prepare)
         {
-          old_map= dbug_tmp_use_all_columns(table, table->write_set);
+          MY_BITMAP *old_map= dbug_tmp_use_all_columns(table, &table->write_set);
           (void) item->save_in_field(key_part->field, 1);
-          dbug_tmp_restore_column_map(table->write_set, old_map);
+          dbug_tmp_restore_column_map(&table->write_set, old_map);
         }
         key_len+= key_part->store_length;
         keypart_map= (keypart_map << 1) | 1;