Attempting to compile xfce4-settings-4.7.3 (on Solaris, but this doesn't look OS specific):

gmake[2]: Entering directory `/var/tmp/xfce47/xfce4-settings-4.7.3/xfce4-settings-helper'
  CC     xfce4_settings_helper-displays.o
displays.c: In function `xfce_displays_helper_init':
displays.c:139: error: structure has no member named `has_1_3'
gmake[2]: *** [xfce4_settings_helper-displays.o] Error 1
gmake[2]: Leaving directory `/var/tmp/xfce47/xfce4-settings-4.7.3/xfce4-settings-helper'
gmake[1]: *** [all-recursive] Error 1