[BUGS] Incorrect type in pg_cast causes Postmaster to core dump

[postgres@efm1 ~]$ cat /etc/redhat-release

CentOS Linux release 7.3.1611 (Core)

[postgres@efm1 ~]$ pg_ctl -c start

server starting

[postgres@efm1 ~]$ < 2017-04-21 11:10:35.287 BST > LOG:  redirecting log output to logging collector process

< 2017-04-21 11:10:35.287 BST > HINT:  Future log output will appear in directory "pg_log".

[postgres@efm1 ~]$ psql

psql (9.6.2)

Type "help" for help.

postgres=# select version();

                                                 version

----------------------------------------------------------------------------------------------------------

 PostgreSQL 9.6.2 on x86_64-pc-linux-gnu, compiled by gcc (GCC) 4.8.5 20150623 (Red Hat 4.8.5-11), 64-bit

(1 row)

postgres=# CREATE FUNCTION bool_to_num (boolean) RETURNS integer

postgres-#     AS 'SELECT CASE WHEN $1 = true THEN 1 ELSE 0 END;'

postgres-#     LANGUAGE SQL

postgres-#     IMMUTABLE

postgres-#     RETURNS NULL ON NULL INPUT;

CREATE FUNCTION

postgres=# select oid from pg_proc where proname = 'bool_to_num';

  oid

-------

 16384

(1 row)

postgres=# SELECT oid, typname FROM pg_type WHERE typname IN ('bool', 'numeric');

 oid  | typname

------+---------

   16 | bool

 1700 | numeric

(2 rows)

postgres=# INSERT INTO pg_cast (castsource, casttarget, castfunc, castcontext, castmethod) VALUES (16,1700,16384,'a','f');

INSERT 16385 1

postgres=# create table bool_test(test_column numeric(22,0));

CREATE TABLE

postgres=# insert into bool_test(test_column) values(true);

server closed the connection unexpectedly

This probably means the server terminated abnormally

before or while processing the request.

The connection to the server was lost. Attempting reset: Failed.

[postgres@efm1 ~]$ ls -al $PGDATA/core.27553

-rw-------. 1 postgres postgres 152203264 Apr 21 11:14 /var/lib/pgsql/9.6/data/core.27553

[postgres@efm1 ~]$ file $PGDATA/core.27553

/var/lib/pgsql/9.6/data/core.27553: ELF 64-bit LSB core file x86-64, version 1 (SYSV), SVR4-style, from 'postgres: postgres postgres', real uid: 1002, effective uid: 1002, real gid: 1002, effective gid: 1002, execfn: '/usr/pgsql-9.6/bin/postgres', platform: 'x86_64'