Re: Trunk emacs infelicity with linum mode

[Eli Zaretskii <eliz@gnu.org>]

> From: Manoj Srivastava <srivasta@ieee.org>
> Date: Wed, 03 Sep 2014 00:06:11 -0700
> 
> > Also, after you load it, do you see the 'linum' face in the buffer
> > popped up by "M-x list-faces-display"?
> 
>         Yes, the face  does exist. I can also see the same face in the
>  line numbers on the left. In previous sessions, I had tried
>  customizing the face, to no avail (I have since removed the
>  customization).

I don't understand how is this possible.  I can only suggest to run
Emacs under GDB, put a breakpoint on the line in  xfaces.c marked below:

  static Lisp_Object
  lface_from_face_name_no_resolve (struct frame *f, Lisp_Object face_name,
				   int signal_p)
  {
    Lisp_Object lface;

    if (f)
      lface = assq_no_quit (face_name, f->face_alist);
    else
      lface = assq_no_quit (face_name, Vface_new_frame_defaults);

    if (CONSP (lface))
      lface = XCDR (lface);
    else if (signal_p)
      signal_error ("Invalid face", face_name);  <<<<<<<<<<<<<<<<<<<<<<

    check_lface (lface);

    return lface;
  }

and then post the backtrace when the breakpoint breaks.

(Please make sure GDB reads the .gdbinit file when you start it, so
that the backtrace includes the Lisp level.)