bug#44850: 27.1; Emacs crash in font handling with font-backend ns

[Eli Zaretskii]

> From: Pieter van Oostrum <pieter-l@vanoostrum.org>
> Date: Thu, 26 Nov 2020 18:26:07 +0100
> Cc: 44850@debbugs.gnu.org, Pieter van Oostrum <pieter@vanoostrum.org>
> 
> The master branch also crashes but with a different error:
> 
> doprnt.c:493: Emacs fatal error: assertion failed: ASCII_CHAR_P (fmtchar)
> 
> Thread 3 hit Breakpoint 1, terminate_due_to_signal (sig=6, 
> backtrace_limit=2147483647)
>     at emacs.c:378
> 378     signal (sig, SIG_DFL);
> (gdb) bt full
> #0  terminate_due_to_signal (sig=6, backtrace_limit=2147483647) at emacs.c:378
> No locals.
> #1  0x000000010029534b in die (msg=0x10051332b "ASCII_CHAR_P (fmtchar)", 
>     file=0x1005132cc "doprnt.c", line=493) at alloc.c:7355
> No locals.
> #2  0x00000001003d61d5 in doprnt (buffer=0x103ec69b0 "Emacs  ", 
> bufsize=9223372036854775801, 
>     format=0x10051ecc5 "%s  —  (%d x %d)", format_end=0x0, ap=0x7ffeefbf62b0) 
> at doprnt.c:493
>         fmt0 = 0x10051ecc9 "—  (%d x %d)"
>         fmtchar = -30 '\342'
>         src = 0x7fff3bc96b21 "windowWillResize:toSize:"
>         srclen = 13637
>         modifier_len = "\000\001\001\001\001"
>         fmt = 0x10051ecca "\200\224  (%d x %d)"
>         bufptr = 0x103ec69b7 ""
>         tembuf = '\000' <repeats 37 times>, "h\224@", '\000' <repeats 13 
> times>, "\210\200\300", '\000' <repeats 14 times>, ".@", '\000' <repeats 46 
> times>, ".@", '\000' <repeats 22 times>, ".@", '\000' <repeats 22 times>, 
> ".@", '\000' <repeats 104 times>...
>         size_allocated = 408
>         sprintf_buffer = 0x7ffeefbf5f70 ""
>         big_buffer = 0x0
>         quoting_style = XIL(0x3ed0)

I believe this is a known problem.