After building recent head, I started to see Args out of range errors occasionally.

 sort: Args out of range: [nil :family :foundry :swidth :height :weight :slant :underline :inverse :foreground ...], 19

I inspected a little, and I think a found the problem.
Commit f9206f34d63104c50659a15d3615646a09df87bf intorduced new LFACE_EXTEND_INDEX enum for lface_attribute_index 
in src/dispextern.h, but probably forgot to add corresponding value to internal-lisp-face-attributes defvar, 
causing an arg-out-of-range error for few face related functions.

After adding :extend keyword to internal-lisp-face-attributes the error don't occur.  

(setq internal-lisp-face-attributes
  [nil
   :family :foundry :swidth :height :weight :slant :underline :inverse
   :foreground :background :stipple :overline :strike :box
   :font :inherit :fontset :vector :extend])