PS 8.0 mysqldump crashes when innodb-optimize-keys used

use test;
create table t1 (a int primary key, b int not null, key k_b(b));
insert into t1 values (1,1),(2,2),(3,3);

### with --innodb-optimize-keys
plavi@bender  ~/lab/mysql/bin/Percona-Server-8.0.12-2-Linux.x86_64  bin/mysqldump --innodb-optimize-keys --socket=/home/plavi/lab/mysql/bin/Percona-Server-8.0.12-2-Linux.x86_64/socket.sock --user root test t1 > backup-optimized.sql
Warning: A partial dump from a server that has GTIDs will by default include the GTIDs of all transactions, even those that changed suppressed parts of the database. If you don't want to restore GTIDs, pass --set-gtid-purged=OFF. To make a complete dump, pass --all-databases --triggers --routines --events.
[1]    1706 segmentation fault  bin/mysqldump --innodb-optimize-keys  --user root test t1 >

# GDB INFO
--
-- Table structure for table `t1`
--
Program received signal SIGSEGV, Segmentation fault.
0x00000000004238b5 in skip_secondary_keys (has_pk=true, create_str=<optimized out>) at ../../../../client/mysqldump.cc:2759
2759    ../../../../client/mysqldump.cc: No such file or directory.

### without --innodb-optimize-keys works ok
plavi@bender  ~/lab/mysql/bin/Percona-Server-8.0.12-2-Linux.x86_64  bin/mysqldump --socket=/home/plavi/lab/mysql/bin/Percona-Server-8.0.12-2-Linux.x86_64/socket.sock --user root test t1 > backup.sql
Warning: A partial dump from a server that has GTIDs will by default include the GTIDs of all transactions, even those that changed suppressed parts of the database. If you don't want to restore GTIDs, pass --set-gtid-purged=OFF. To make a complete dump, pass --all-databases --triggers --routines --events.

# with --innodb-optimize-keys
plavi@bender  ~/lab/mysql/bin/Percona-Server-5.7.23-23-Linux.x86_64.ssl102  bin/mysqldump --innodb-optimize-keys --socket=/home/plavi/lab/mysql/bin/Percona-Server-5.7.23-23-Linux.x86_64.ssl102/socket.sock --user root test t1 > backup-optimized.sql

# without --innodb-optimize-keys
plavi@bender  ~/lab/mysql/bin/Percona-Server-5.7.23-23-Linux.x86_64.ssl102  bin/mysqldump --socket=/home/plavi/lab/mysql/bin/Percona-Server-5.7.23-23-Linux.x86_64.ssl102/socket.sock --user root test t1 > backup.sql

# file diff to prove that key generation was added after table create
plavi@bender  ~/lab/mysql/bin/Percona-Server-5.7.23-23-Linux.x86_64.ssl102  diff backup.sql backup-optimized.sql
37,38c37
<   PRIMARY KEY (`a`),
<   KEY `k_b` (`b`)
---
>   PRIMARY KEY (`a`)
48a48
> ALTER TABLE `t1` ADD KEY `k_b` (`b`);
65c65
< -- Dump completed on 2018-10-29 14:34:47
---
> -- Dump completed on 2018-10-29 14:34:31