Ruby: missing Directory Reference

Ruby 4.0.6p0 (2026-07-14 revision 03b6d3f8898a28604fe6cb00eae3226b821168f4)

missing Directory Reference

## Files
| acosh.c
| alloca.c
| cbrt.c
| close.c
| crt_externs.h
| crypt.c
| crypt.h
| des_tables.c
| dtoa.c
| erf.c
| explicit_bzero.c
| ffs.c
| file.h
| flock.c
| hypot.c
| langinfo.c
| lgamma_r.c
| memcmp.c
| memmove.c
| mt19937.c
| nan.c
| nextafter.c
| procstat_vm.c
| setproctitle.c
| strchr.c
| strerror.c
| strlcat.c
| strlcpy.c
| strstr.c
| tgamma.c