GNU bug report logs - #45898
27.1; wedged in redisplay again

Previous Next

Full log

View this message in rfc822 format

From: Devon Sean McCullough <Emacs-hacker2018 <at> jovi.net>
To: 45898 <at> debbugs.gnu.org
Subject: bug#45898: 27.1; wedged in redisplay again
Date: Fri, 15 Jan 2021 13:13:16 -0500

An elisp expression output a bigger list than expected so I hit m-< and
went out for a walk.  After four hours of 99% CPU, lldb backtrace shows

main → Frecursive_edit → recursive_edit_1 → command_loop →
command_loop.cold.1 → internal_catch → command_loop_2 →
internal_condition_case → command_loop_1 → read_key_sequence → read_char
→ redisplay_internal → redisplay_windows → redisplay_windows →
internal_condition_case_1 → redisplay_window_0 → redisplay_window →
compute_window_start_on_continuation_line → move_it_to →
move_it_in_display_line_to → gui_produce_glyphs → macfont_encode_char

If lldb forces read_char to return Qnil or redisplay_internal to return,
will Emacs crash immediately or survive long enough to save all buffers
or better yet continue working?

Would calling Fgoto-char(Fpoint_min()) from the lldb break immediately 
corrupt or crash Emacs?

	Peace
		--Devon

P.S.  If there exists a way to quickly and safely abort redisplay,
perhaps there should be a hook invoked when repeated keyboard-quit
has no effect, allowing experimentation into workarounds for this
apparently intractable redisplay problem?

Previous Next

GNU bug tracking system
Copyright (C) 1999 Darren O. Benham, 1997,2003 nCipher Corporation Ltd, 1994-97 Ian Jackson.