This will overwrite data on /dev/sdb irrevocably.

Are you sure? (Type uppercase yes): YES

Program received signal SIGSEGV, Segmentation fault.
0x00007ffff7263da1 in __strlen_sse2 () from /lib64/libc.so.6
(gdb) backtrace
#0  0x00007ffff7263da1 in __strlen_sse2 () from /lib64/libc.so.6
#1  0x00007ffff724a30c in puts () from /lib64/libc.so.6
#2  0x0000000000405c68 in printf (__fmt=<synthetic pointer>) at /usr/include/bits/stdio2.h:104
#3  tools_get_key (prompt=0x40a036 "Enter passphrase: ", key=key@entry=0x7fffffffe188, key_size=key_size@entry=0x7fffffffe190, keyfile_offset=keyfile_offset@entry=0, keyfile_size_max=keyfile_size_max@entry=0,
    key_file=key_file@entry=0x0, timeout=timeout@entry=0, verify=verify@entry=1, pwquality=pwquality@entry=1, key_description=key_description@entry=0x0, key_type=key_type@entry=0x40a930 "user",
    cd=cd@entry=0x613790) at utils_password.c:86
#4  0x00000000004086ab in action_luksFormat () at cryptsetup.c:734
#5  0x00000000004034eb in run_action (action=<optimized out>) at cryptsetup.c:1459
#6  main (argc=3, argv=0x7fffffffe428) at cryptsetup.c:1754
(gdb)