Integer & glyph (trunk and emacs_unicode)

[Vinicius Jose Latorre]

It seems that glyphs have some problems as it's implemented
by make-glyph-code, glyph-char and glyph-face in disp-table.el file.

The integers in Emacs Lisp have a minimum range from -2**28 to
2**28 - 1, that is, 29 bits.  In my system (AMD Athlon 64 -
GNU/Linux Debian using Emacs 23.0.50.1 - CVS trunk) integers
in Emacs Lisp have 29 bits.

The make-glyph-code in Emacs 23.0.50.1 (CVS trunk) is:

(defun make-glyph-code (char &optional face)
  "Return a glyph code representing char CHAR with face FACE."
  ;; Due to limitations on Emacs integer values, faces with
  ;; face id greater that 4091 are silently ignored.
  (if (and face (<= (face-id face) #xfff))
      (logior char (lsh (face-id face) 19))
    char))

So, it assumes 12 bits for face id and 19 bits for char code,
the result is an integer of 31 bits.

Shouldn't it be used #x3ff (10 bits for face id) instead of #xfff?

BTW, the same thing happens in Emacs unicode branch.