DragonFlyBSD

The stat(2) man page claims:

st_ctim       Time when file status was last changed (inode data
                   modification).  Changed by the chmod(2), chown(2), link(2),
                   mknod(2), rename(2), unlink(2), utimes(2) and write(2)
                   system calls.

but neither link() nor chmod() update ctim.tv_sec:

$ pwd
  /home/tony/dev/perl/git/dflybugs
  $ cc -olink_ctime link_ctime.c
  $ ./link_ctime
  FAIL: chmod didn't update ctime
  FAIL: link didn't update ctime
  $ mount
  serno/VB6e53d937-50b8dc58.s1d on / (hammer2, local)
  devfs on /dev (devfs, nosymfollow, local)
  /dev/serno/VB6e53d937-50b8dc58.s1a on /boot (ufs, local)
  /build/usr.obj on /usr/obj (null)
  /build/var.crash on /var/crash (null)
  /build/var.cache on /var/cache (null)
  /build/var.spool on /var/spool (null)
  /build/var.log on /var/log (null)
  /build/var.tmp on /var/tmp (null)
  tmpfs on /tmp (tmpfs, local)
  procfs on /proc (procfs, local)
  tmpfs on /var/run/shm (tmpfs, local)
  $ uname -a
  DragonFly  5.8-RELEASE DragonFly v5.8.3-RELEASE #10: Thu Sep 24 19:19:45 EDT 2020     root@www.shiningsilence.com:/usr/obj/home/justin/release/5_8/sys/X86_64_GENERIC  x86_64

link_ctime.c is attached.