Inconsistent handling and crash with 0-length PRIMARY KEY

--source include/have_innodb.inc

CREATE TABLE t (a INT KEY,b INT)Engine=Innodb;

ALTER TABLE t ADD INDEX (a);

ALTER TABLE t CHANGE COLUMN a a BINARY (0);

EXPLAIN PARTITIONS SELECT * FROM t WHERE a<='';

Core was generated by `/test/MD080126-mariadb-11.4.10-linux-x86_64-dbg/bin/mariadbd --no-defaults --ma'.

Program terminated with signal SIGFPE, Arithmetic exception.

#0  0x00005d94788a7615 in handler::multi_range_read_info_const (this=0x7e799406dcc8, keyno=1, seq=0x7e7abc563bd0, seq_init_param=0x7e7abc563bf8, n_ranges_arg=0, bufsz=0x7e7abc563a68, flags=0x7e7abc563a6c, top_limit=18446744073709551615, cost=0x7e7abc564268)at /test/11.4_dbg/sql/multi_range_read.cc:193

193	  size_t avg_block_records= ((uint) (stats.block_size*3/4))/len + 1;

[Current thread is 1 (LWP 1738061)]

(gdb) bt

#0  0x00005d94788a7615 in handler::multi_range_read_info_const (this=0x7e799406dcc8, keyno=1, seq=0x7e7abc563bd0, seq_init_param=0x7e7abc563bf8, n_ranges_arg=0, bufsz=0x7e7abc563a68, flags=0x7e7abc563a6c, top_limit=18446744073709551615, cost=0x7e7abc564268)at /test/11.4_dbg/sql/multi_range_read.cc:193

#1  0x00005d94788ab22b in DsMrr_impl::dsmrr_info_const (this=0x7e799406e210, keyno=1, seq=0x7e7abc563bd0, seq_init_param=0x7e7abc563bf8, n_ranges=0, bufsz=0x7e7abc564258, flags=0x7e7abc56425c, limit=18446744073709551615, cost=0x7e7abc564268) at /test/11.4_dbg/sql/multi_range_read.cc:1795

#2  0x00005d9478e72196 in ha_innobase::multi_range_read_info_const (this=0x7e799406dcc8, keyno=1, seq=0x7e7abc563bd0, seq_init_param=0x7e7abc563bf8, n_ranges=0, bufsz=0x7e7abc564258, flags=0x7e7abc56425c, limit=18446744073709551615, cost=0x7e7abc564268)at /test/11.4_dbg/storage/innobase/handler/ha_innodb.cc:20114

#3  0x00005d947850aec4 in check_quick_select (param=0x7e7abc5648e0, idx=1, limit=18446744073709551615, index_only=false, tree=0x7e7994088670, update_tbl_stats=true, mrr_flags=0x7e7abc56425c, bufsize=0x7e7abc564258, cost=0x7e7abc564268, is_ror_scan=0x7e7abc564257)at /test/11.4_dbg/sql/opt_range.cc:12136

#4  0x00005d94784ec363 in get_key_scans_params (param=0x7e7abc5648e0, tree=0x7e7994088568, index_read_must_be_used=false, for_range_access=true, read_time=0.0026289099999999999, limit=18446744073709551615, using_table_scan=false) at /test/11.4_dbg/sql/opt_range.cc:7861

#5  0x00005d94784eae23 in SQL_SELECT::test_quick_select (this=0x7e799401dee8, thd=0x7e7994000d58, keys_to_use={static BITS_PER_ELEMENT = 64, static ARRAY_ELEMENTS = 1, static ALL_BITS_SET = 18446744073709551615, buffer = {3}}, prev_tables=0, limit=18446744073709551615, force_quick_range=false, ordered_output=false, remove_false_parts_of_where=true, only_single_index_range_scan=false, note_unusable_keys=Item_func::BITMAP_EXCEPT_ANY_EQUALITY)at /test/11.4_dbg/sql/opt_range.cc:3001

#6  0x00005d947872deab in get_quick_record_count (thd=0x7e7994000d58, select=0x7e799401dee8, table=0x7e7994014ac8, keys=0x7e799401ca50, limit=18446744073709551615, quick_count=0x7e7abc565428)at /test/11.4_dbg/sql/sql_select.cc:5477

#7  0x00005d94786e6bef in make_join_statistics (join=0x7e799401bd50, tables_list=@0x7e7994019d50: {<base_list> = {<Sql_alloc> = {<No data fields>}, first = 0x7e799401c510, last = 0x7e799401c510, elements = 1}, <No data fields>}, keyuse_array=0x7e799401c0b0) at /test/11.4_dbg/sql/sql_select.cc:6261

#8  0x00005d94786de9b8 in JOIN::optimize_inner (this=0x7e799401bd50)at /test/11.4_dbg/sql/sql_select.cc:2744

#9  0x00005d94786dc3ed in JOIN::optimize (this=0x7e799401bd50)at /test/11.4_dbg/sql/sql_select.cc:2016

#10 0x00005d94786d4268 in mysql_select (thd=0x7e7994000d58, tables=0x7e799401a170, fields=@0x7e7994019df0: {<base_list> = {<Sql_alloc> = {<No data fields>}, first = 0x7e799401a120, last = 0x7e799401c790, elements = 2}, <No data fields>}, conds=0x7e799401aa40, og_num=0, order=0x0, group=0x0, having=0x0, proc_param=0x0, select_options=2164525828, result=0x7e799401b600, unit=0x7e7994005018, select_lex=0x7e7994019b38)at /test/11.4_dbg/sql/sql_select.cc:5402

#11 0x00005d947872708d in mysql_explain_union (thd=0x7e7994000d58, unit=0x7e7994005018, result=0x7e799401b600)at /test/11.4_dbg/sql/sql_select.cc:31569

#12 0x00005d947867aba3 in execute_sqlcom_select (thd=0x7e7994000d58, all_tables=0x7e799401a170) at /test/11.4_dbg/sql/sql_parse.cc:6163

#13 0x00005d947866ff02 in mysql_execute_command (thd=0x7e7994000d58, is_called_from_prepared_stmt=false) at /test/11.4_dbg/sql/sql_parse.cc:3987

#14 0x00005d9478668084 in mysql_parse (thd=0x7e7994000d58, rawbuf=0x7e7994019a80 "EXPLAIN PARTITIONS SELECT * FROM t WHERE a<=''", length=46, parser_state=0x7e7abc567a30)at /test/11.4_dbg/sql/sql_parse.cc:7945

#15 0x00005d9478665519 in dispatch_command (command=COM_QUERY, thd=0x7e7994000d58, packet=0x7e799400af89 "", packet_length=46, blocking=true) at /test/11.4_dbg/sql/sql_parse.cc:1923

#16 0x00005d9478668c33 in do_command (thd=0x7e7994000d58, blocking=true)at /test/11.4_dbg/sql/sql_parse.cc:1433

#17 0x00005d947884d159 in do_handle_one_connection (connect=0x5d94aa740458, put_in_cache=true) at /test/11.4_dbg/sql/sql_connect.cc:1497

#18 0x00005d947884cef2 in handle_one_connection (arg=0x5d94aa77cdf8)at /test/11.4_dbg/sql/sql_connect.cc:1409

#19 0x00007e7abfc9caa4 in start_thread (arg=<optimized out>)at ./nptl/pthread_create.c:447

#20 0x00007e7abfd29c6c in clone3 ()at ../sysdeps/unix/sysv/linux/x86_64/clone3.S:78

    Rel    o/d  Build   Commit                                    UniqueID observed             

CS  10.6   dbg  080126  635a8500ed8d62763ac57c26b2de821f255c84b0  SIGFPE|handler::multi_range_read_info_const|DsMrr_impl::dsmrr_info_const|ha_innobase::multi_range_read_info_const|check_quick_select

CS  10.6   opt  080126  635a8500ed8d62763ac57c26b2de821f255c84b0  SIGFPE|handler::multi_range_read_info_const|DsMrr_impl::dsmrr_info_const|check_quick_select|get_key_scans_params

CS  10.11  dbg  080126  15e4ae4a91a6bda41a6bb036cb105ba104c731e9  SIGFPE|handler::multi_range_read_info_const|DsMrr_impl::dsmrr_info_const|ha_innobase::multi_range_read_info_const|check_quick_select

CS  10.11  opt  080126  15e4ae4a91a6bda41a6bb036cb105ba104c731e9  SIGFPE|handler::multi_range_read_info_const|DsMrr_impl::dsmrr_info_const|check_quick_select|get_key_scans_params

CS  11.4   dbg  080126  ab2e0d4f0d27803fb331b9d052f0dfe711a0e60c  SIGFPE|handler::multi_range_read_info_const|DsMrr_impl::dsmrr_info_const|ha_innobase::multi_range_read_info_const|check_quick_select

CS  11.4   opt  080126  ab2e0d4f0d27803fb331b9d052f0dfe711a0e60c  SIGFPE|handler::multi_range_read_info_const|DsMrr_impl::dsmrr_info_const|check_quick_select|get_key_scans_params

CS  11.8   dbg  080126  afbad3b02bdcb0ed98789311632c7f87268322ed  SIGFPE|handler::multi_range_read_info_const|DsMrr_impl::dsmrr_info_const|ha_innobase::multi_range_read_info_const|check_quick_select

CS  11.8   opt  080126  afbad3b02bdcb0ed98789311632c7f87268322ed  SIGFPE|handler::multi_range_read_info_const|DsMrr_impl::dsmrr_info_const|check_quick_select|get_key_scans_params

CS  12.3   dbg  080126  e19be4919fec58a70c88023bcb1f88793fb4c90e  SIGFPE|handler::multi_range_read_info_const|DsMrr_impl::dsmrr_info_const|ha_innobase::multi_range_read_info_const|check_quick_select

CS  12.3   opt  080126  e19be4919fec58a70c88023bcb1f88793fb4c90e  SIGFPE|handler::multi_range_read_info_const|DsMrr_impl::dsmrr_info_const|check_quick_select|get_key_scans_params

ES  10.6   dbg  080126  0fe345fff3a0463224ca714831303d40fb83648b  SIGFPE|handler::multi_range_read_info_const|DsMrr_impl::dsmrr_info_const|ha_innobase::multi_range_read_info_const|check_quick_select

ES  10.6   opt  080126  0fe345fff3a0463224ca714831303d40fb83648b  SIGFPE|handler::multi_range_read_info_const|DsMrr_impl::dsmrr_info_const|check_quick_select|get_key_scans_params

ES  11.4   dbg  080126  34f616d5fd2c649d0c79acb4e2423c90b8f10436  SIGFPE|handler::multi_range_read_info_const|DsMrr_impl::dsmrr_info_const|ha_innobase::multi_range_read_info_const|check_quick_select

ES  11.4   opt  080126  34f616d5fd2c649d0c79acb4e2423c90b8f10436  SIGFPE|handler::multi_range_read_info_const|DsMrr_impl::dsmrr_info_const|check_quick_select|get_key_scans_params

ES  11.8   dbg  080126  405ee76b60c4ab82155f339136ed20d3b7363717  SIGFPE|handler::multi_range_read_info_const|DsMrr_impl::dsmrr_info_const|ha_innobase::multi_range_read_info_const|check_quick_select

ES  11.8   opt  080126  405ee76b60c4ab82155f339136ed20d3b7363717  SIGFPE|handler::multi_range_read_info_const|DsMrr_impl::dsmrr_info_const|check_quick_select|get_key_scans_params