Re: MPS: face-cache

[Gerd Möllmann]

Gerd Möllmann <gerd.moellmann@gmail.com> writes:

> Gerd Möllmann <gerd.moellmann@gmail.com> writes:
>
>> Helmut Eller <eller.helmut@gmail.com> writes:
>>
>>> On Sun, Apr 28 2024, Gerd Möllmann wrote:
>>>
>>>> Wow! I'm an idiot. All three thumbs up! Did you already try it?
>>>
>>> Yes. My test case is this
>>>
>>> set args -Q -eval '(progn (view-hello-file) (while t (redisplay) 
>>> (igc--collect) (forward-line)))'
>>>
>>> It goes now a few lines further before it hits the next issue.
>>
>> Hm, yeah. I've oused that, BTW.
>
> Ok, it's an assertion in font_has_char for me.
>
> (lldb) p font
> (Lisp_Object) 0x000000010320c8b5 (struct Lisp_Vector *) $7 = 
> 0x000000010320c8b0
> (lldb) p *(struct igc_header *) ((char *) $7 - 8)
> (struct igc_header)  (obj_type = IGC_OBJ_FWD, pvec_type = PVEC_FONT, hash = 
> 174276, nwords = 16)
>
> The header says the object gas been moved (IGC_OBJ_FWD), which should
> mean that the reference from where font comes hasn't been traced
> (otherwise it wouldn't point to the tombstone.

Someone knows something about this in struct frame?

  /* List of font-drivers available on the frame.  */
  struct font_driver_list *font_driver_list;

Looks to me that the font objecz could come from there. Alas, I don't
remember anything about font drivers. I don't think we had that in the
good old times.