bug#45927: Emacs hangs every few week due to xim

[Joey Green]

Hi, My emacs hangs every few days, even with emacs -Q, I've attached gdb to it while crashing and got the following backtrace:

searene@archlinux:~$ sudo gdb attach 14210
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    Type "apropos word" to search for commands related to "word"...
    attach: No such file or directory.
    Attaching to process 14210
    [New LWP 14212]
    [New LWP 14216]
    [New LWP 14217]
    [Thread debugging using libthread_db enabled]
    Using host libthread_db library "/usr/lib/libthread_db.so.1".
    0x00007f569cd2046f in poll () from /usr/lib/libc.so.6
    (gdb) bt full
    #0  0x00007f569cd2046f in poll () at /usr/lib/libc.so.6
    #1  0x00007f569dfd263b in  () at /usr/lib/libxcb.so.1
    #2  0x00007f569dfd437b in xcb_wait_for_event () at /usr/lib/libxcb.so.1
    #3  0x00007f569e038209 in _XReadEvents () at /usr/lib/libX11.so.6
    #4  0x00007f569e01f396 in XIfEvent () at /usr/lib/libX11.so.6
    #5  0x00007f569e068ca0 in  () at /usr/lib/libX11.so.6
    #6  0x00007f569e0699d2 in  () at /usr/lib/libX11.so.6
    #7  0x00007f569e069c6c in _XimRead () at /usr/lib/libX11.so.6
    #8  0x00007f569e0583ce in  () at /usr/lib/libX11.so.6
    #9  0x00007f569e045955 in XSetICValues () at /usr/lib/libX11.so.6
    #10 0x0000561ace6df9b3 in  ()
    #11 0x0000561ace6627a7 in  ()
    #12 0x0000561ace61e5a5 in  ()
    #13 0x0000561ace61eb33 in  ()
    #14 0x0000561ace61ffdb in  ()
    #15 0x0000561ace6201fb in  ()
    #16 0x0000561ace659154 in  ()
    #17 0x0000561ace65a6b5 in  ()
    #18 0x0000561ace7054ff in  ()
    #19 0x0000561ace7bc9e0 in  ()
    #20 0x0000561ace6210d3 in  ()
    #21 0x0000561ace707efd in  ()
    #22 0x0000561ace708928 in  ()
    #23 0x0000561ace70a06f in  ()
    #24 0x0000561ace7779e7 in  ()
    #25 0x0000561ace6fae65 in  ()
    #26 0x0000561ace777942 in  ()
    #27 0x0000561ace6fadfd in  ()
    #28 0x0000561ace70040b in  ()
    #29 0x0000561ace700734 in  ()
    --Type <RET> for more, q to quit, c to continue without paging--
    #30 0x0000561ace616de1 in  ()
    #31 0x00007f569cc53152 in __libc_start_main () at /usr/lib/libc.so.6
    #32 0x0000561ace61753e in  ()

Seems like it's due to xim. I tried to disable xim by adding the following line to ~/.Xresources

emacs*useXIM: false

The hanging doesn't occur again. But I cannot input with my input method(fcitx) as well, this is a huge problem for me. I want to see if there's a solution for it. Even a method to unblock it is helpful, otherwise I have to kill Emacs and recover-session each time, which sometimes can cause data loss.

My related installed packages info:

fcitx

- fcitx 4.2.9.8-1

- fcitx-configtool 0.4.10-4

- fcitx-sogoupinyin 2.4.0.2732-1

ArchLinuxLinux

- ArchLinux 5.10.6-arch1-1 #1 SMP PREEMPT Sat, 09 Jan 2021 18:22:35 +0000 x86_64 GNU/Linux

Here are some related issues I found online about this, seems to be an old bug:

- https://bugzilla.redhat.com/show_bug.cgi?id=452849

- https://lists.gnu.org/archive/html/bug-gnu-emacs/2017-07/msg00520.html

Other info carried by Emacs' report-emacs-bugs:

In GNU Emacs 27.1 (build 1, x86_64-pc-linux-gnu, GTK+ Version 3.24.22, cairo version 1.17.3)
 of 2020-08-29 built on juergen
Windowing system distributor 'The X.Org Foundation', version 11.0.12010000
System Description: Arch Linux

Recent messages:
Restarting server
(org-roam) total: 

Please tell me if you need more info.