Comment 2 for bug 1741227

libopts is of autogen
See
autogen-5.18.12/autoopts/autoopts.c

Note for gdb on affected systems:
(gdb) catch syscall open
(gdb) run -p /var/run/ntpd.pid -g -c /run/ntp.conf.dhcp -u 112:116

dbg on libopts is odd
get from https://launchpad.net/ubuntu/bionic/amd64/libopts25-dbgsym/1:5.18.12-3

Now Details are better:
#0 0x00007fd4f489fd53 in __opendir (name=name@entry=0x7fff724da8d0 "/usr/local/sbin") at ../sysdeps/posix/opendir.c:191
#1 0x00007fd4f5569ba7 in option_pathfind (path=0x7fff724ddf82 "/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/snap/bin",
    fname=fname@entry=0x7fff724dd836 "/usr/sbin/ntpd", mode=<synthetic pointer>) at ../compat/pathfind.c:61
#2 0x00007fd4f5570de6 in validate_struct (opts=opts@entry=0x55a84db841e0 <ntpdOptions>, pname=0x7fff724dd836 "/usr/sbin/ntpd") at init.c:108
#3 0x00007fd4f5572a4f in optionProcess (opts=0x55a84db841e0 <ntpdOptions>, a_ct=8, a_v=0x7fff724dbff8) at autoopts.c:335
#4 0x000055a84d8e8e7f in parse_cmdline_opts (pargc=0x7fff724dba1c, pargv=0x7fff724dba10) at ntpd.c:359
#5 0x000055a84d8e8f8d in ntpdmain (argc=<optimized out>, argv=<optimized out>) at ntpd.c:575
#6 0x00007fd4f47ed1c1 in __libc_start_main (main=0x55a84d8d90e0 <main>, argc=8, argv=0x7fff724dbff8, init=<optimized out>,
    fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7fff724dbfe8) at ../csu/libc-start.c:308