the crash is at an atexit() handler indeed, but gnome-settings-daemon doesn't install any, so I guess it might be an external g-s-d plugin or one of the libraries used in g-s-d. So, once we get the output of that 'ls' command, we'll see what -debug package to install, to get better information of what exit handler is making g-s-d crash
If you can easily reproduce, can you please run:
$ ls /usr/lib/ gnome-settings- daemon- 3.0/
the crash is at an atexit() handler indeed, but gnome-settings- daemon doesn't install any, so I guess it might be an external g-s-d plugin or one of the libraries used in g-s-d. So, once we get the output of that 'ls' command, we'll see what -debug package to install, to get better information of what exit handler is making g-s-d crash