bug#30519: 26.0.91; Emacs hangs with flyspell overlay

[Nick Helm]

On Tue, 20 Feb 2018 at 17:06:00 +1300, Eli Zaretskii wrote:

> A C- and Lisp-level backtrace from the place which signals that error
> would be helpful.

Is this any use?

(lldb)  bt
  thread #4, name = 'org.gnu.Emacs.lisp-main', stop reason = breakpoint 1.1
    frame #0: 0x00000001002fd0b2 Emacs`Fsignal(error_symbol=(i = 21936), 
data=(i = 4320849923)) at eval.c:1520
    frame #1: 0x00000001001b6d2d Emacs`xsignal(error_symbol=(i = 21936), 
data=(i = 4320849923)) at lisp.h:3861
    frame #2: 0x00000001002f545a Emacs`xsignal1(error_symbol=(i = 21936), 
arg=(i = 4344323516)) at eval.c:1654
    frame #3: 0x00000001002fd99e Emacs`verror(m="Marker does not point 
anywhere", ap=0x000070000b94eca0) at eval.c:1839
    frame #4: 0x00000001002f51d9 Emacs`error(m="Marker does not point 
anywhere") at eval.c:1851
    frame #5: 0x000000010022e83e Emacs`marker_position(marker=(i = 4390033497)) 
at marker.c:641
    frame #6: 0x000000010020e668 Emacs`mouse_face_overlay_overlaps(overlay=(i = 
4390033257)) at buffer.c:3058
    frame #7: 0x000000010009140d 
Emacs`note_mouse_highlight(f=0x0000000107060f38, x=25, y=5) at xdisp.c:31421
    frame #8: 0x000000010041c047 
Emacs`mac_frame_up_to_date(f=0x0000000107060f38) at macterm.c:938
    frame #9: 0x0000000100068763 Emacs`redisplay_internal at xdisp.c:14546
    frame #10: 0x000000010006baa7 
Emacs`redisplay_preserve_echo_area(from_where=5) at xdisp.c:14658
    frame #11: 0x00000001001c7721 Emacs`read_char(commandflag=1, map=(i = 
4320851891), prev_event=(i = 0), used_mouse_menu=0x000070000b95308f, 
end_time=0x0000000000000000) at keyboard.c:2501
    frame #12: 0x00000001001c20f6 
Emacs`read_key_sequence(keybuf=0x000070000b953600, bufsize=30, prompt=(i = 0), 
dont_downcase_last=false, can_return_switch_frame=true, 
fix_current_buffer=true, prevent_redisplay=false) at keyboard.c:9238
    frame #13: 0x00000001001c080c 
Emacs`__command_loop_1_block_invoke((null)=<unavailable>) at keyboard.c:1381
    frame #14: 0x0000000100479002 
Emacs`mac_autorelease_loop(body=0x00000001001c0380) at macappkit.m:997
    frame #15: 0x00000001001c0212 Emacs`command_loop_1 at keyboard.c:1308
    frame #16: 0x00000001002fcadf 
Emacs`internal_condition_case(bfun=(Emacs`command_loop_1 at keyboard.c:1259), 
handlers=(i = 21936), hfun=(Emacs`cmd_error at keyboard.c:938)) at eval.c:1332
    frame #17: 0x00000001001dd3b1 Emacs`command_loop_2(ignore=(i = 0)) at 
keyboard.c:1110
    frame #18: 0x00000001002fbcc8 Emacs`internal_catch(tag=(i = 52800), 
func=(Emacs`command_loop_2 at keyboard.c:1106), arg=(i = 0)) at eval.c:1097
    frame #19: 0x00000001001bf165 Emacs`command_loop at keyboard.c:1089
    frame #20: 0x00000001001bef77 Emacs`recursive_edit_1 at keyboard.c:695
    frame #21: 0x00000001001bf3ba Emacs`Frecursive_edit at keyboard.c:766
    frame #22: 0x00000001001bc98d Emacs`emacs_main(argc=1, 
argv=0x00007ffeefbffa90) at emacs.c:1750
    frame #23: 0x00000001004c0caa 
Emacs`mac_start_lisp_main(arg=0x00007ffeefbffa90) at macappkit.m:15093
    frame #24: 0x00007fff755216c1 libsystem_pthread.dylib`_pthread_body + 340
    frame #25: 0x00007fff7552156d libsystem_pthread.dylib`_pthread_start + 377
    frame #26: 0x00007fff75520c5d libsystem_pthread.dylib`thread_start + 13

Process 648 stopped
* thread #4, name = 'org.gnu.Emacs.lisp-main', stop reason = breakpoint 1.1
    frame #0: 0x00000001002fd0b2 Emacs`Fsignal(error_symbol=(i = 21936), 
data=(i = 4320849923)) at eval.c:1520
   1517        attributes: noreturn)
   1518   (Lisp_Object error_symbol, Lisp_Object data)
   1519 {
-> 1520   signal_or_quit (error_symbol, data, false);
   1521   eassume (false);
   1522 }
   1523 
Target 0: (Emacs) stopped.
(lldb)