bug#72025: SEGFAULT when using corfu and lsp-mode with clangd

[Ravi D'Elia <ravijdelia@gmail.com>]

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At unpredictable times while editing c++ files, emacs will segfault.
I haven't been able to reproduce without lsp-mode, but with how
unpredictable this is I don't think that necessarily means much.
The problem exists with and without native compilation- this
report assumes without.

STEPS TO REPRODUCE:
- Let '~/minimal' contain the attached init file
- Start emacs with 'emacs --init-directory ~/minimal'
- Open a c++ file
- Edit it, taking care to type quickly and go back to edit within
   words. I can usually get a crash within 10 minutes, but I haven't
   been able to iterate enough to figure out exactly what is
   happening. It's always while typing though, I think in response
   to a keydown.

Attached is the init file I used to reproduce this, and the backtrace.
I had issues with the .gdbinit, which I will hopefully address when
I get back from vacation.

Below is the information from report-emacs-bug:

In GNU Emacs 29.4 (build 1, x86_64-pc-linux-gnu, GTK+ Version 3.24.42,
cairo version 1.18.0)
Windowing system distributor 'The X.Org Foundation', version 11.0.12101013
System Description: Arch Linux

Configured using:
  'configure --sysconfdir=/etc --prefix=/usr --libexecdir=/usr/lib
  --with-tree-sitter --localstatedir=/var --with-cairo
  --disable-build-details --with-harfbuzz --with-libsystemd
  --with-modules --with-x-toolkit=gtk3 'CFLAGS=-march=x86-64
  -mtune=generic -O2 -pipe -fno-plt -fexceptions -Wp,-D_FORTIFY_SOURCE=3
  -Wformat -Werror=format-security -fstack-clash-protection
  -fcf-protection -fno-omit-frame-pointer -mno-omit-leaf-frame-pointer -g
  -ffile-prefix-map=/build/emacs/src=/usr/src/debug/emacs -flto=auto'
  'LDFLAGS=-Wl,-O1 -Wl,--sort-common -Wl,--as-needed -Wl,-z,relro
  -Wl,-z,now -Wl,-z,pack-relative-relocs -flto=auto''

Configured features:
ACL CAIRO DBUS FREETYPE GIF GLIB GMP GNUTLS GPM GSETTINGS HARFBUZZ JPEG
JSON LCMS2 LIBOTF LIBSYSTEMD LIBXML2 M17N_FLT MODULES NOTIFY INOTIFY
PDUMPER PNG RSVG SECCOMP SOUND SQLITE3 THREADS TIFF TOOLKIT_SCROLL_BARS
TREE_SITTER WEBP X11 XDBE XIM XINPUT2 XPM GTK3 ZLIB

Important settings:
   value of $LANG: en_US.UTF-8
   locale-coding-system: utf-8-unix

Major mode: Fundamental

Minor modes in effect:
   corfu-echo-mode: t
   global-corfu-mode: t
   override-global-mode: t
   tooltip-mode: t
   global-eldoc-mode: t
   show-paren-mode: t
   electric-indent-mode: t
   mouse-wheel-mode: t
   tool-bar-mode: t
   menu-bar-mode: t
   file-name-shadow-mode: t
   global-font-lock-mode: t
   blink-cursor-mode: t
   buffer-read-only: t
   line-number-mode: t
   indent-tabs-mode: t
   transient-mark-mode: t
   auto-composition-mode: t
   auto-encryption-mode: t
   auto-compression-mode: t

Load-path shadows:
/usr/share/emacs/site-lisp/xscheme hides /usr/share/emacs/29.4/lisp/progmodes/xscheme

Features:
(shadow sort mail-extr emacsbug message yank-media dired dired-loaddefs
rfc822 mml mml-sec epa derived gnus-util mm-decode mm-bodies mm-encode
mail-parse rfc2231 mailabbrev gmm-utils mailheader sendmail rfc2047
rfc2045 ietf-drums mm-util mail-prsvr mail-utils flymake-cc time-date
flymake-proc flymake warnings lsp-diagnostics lsp-headerline lsp-icons
lsp-modeline lsp-lens view lsp-zig lsp-yang lsp-yaml lsp-xml lsp-wgsl
lsp-volar lsp-vimscript lsp-vhdl lsp-vetur lsp-html lsp-verilog lsp-vala
lsp-v lsp-typeprof lsp-ttcn3 lsp-trunk lsp-toml lsp-tilt lsp-tex
lsp-terraform lsp-svelte lsp-steep lsp-sqls lsp-sql lsp-sorbet
lsp-solidity lsp-solargraph lsp-semgrep lsp-rust lsp-ruff-lsp
lsp-ruby-syntax-tree lsp-ruby-lsp lsp-rubocop lsp-roslyn lsp-rf
lsp-remark lsp-racket lsp-r lsp-qml lsp-pylsp lsp-pyls lsp-pwsh
lsp-purescript lsp-pls lsp-php lsp-perlnavigator lsp-perl lsp-openscad
lsp-ocaml lsp-nushell lsp-nix lsp-nim lsp-nginx lsp-move lsp-mojo
lsp-mint lsp-meson lsp-mdx lsp-marksman lsp-markdown lsp-magik lsp-lua
lsp-lisp lsp-kotlin lsp-json lsp-jq lsp-javascript lsp-idris lsp-haxe
lsp-hack lsp-groovy lsp-graphql lsp-golangci-lint lsp-glsl lsp-gleam
lsp-gdscript lsp-fsharp lsp-fortran lsp-eslint lsp-erlang lsp-emmet
lsp-elm lsp-elixir lsp-earthly lsp-dockerfile lsp-dhall lsp-d lsp-cypher
lsp-cucumber lsp-css lsp-csharp gnutls lsp-crystal lsp-credo lsp-cobol
lsp-cmake lsp-clojure lsp-clangd dom lsp-bufls lsp-go lsp-completion
lsp-beancount lsp-bash lsp-awk lsp-autotools lsp-astro lsp-asm
lsp-ansible lsp-angular lsp-ada lsp-semantic-tokens lsp-actionscript
lsp-mode lsp-protocol xref project tree-widget wid-edit spinner pcase
network-stream puny nsm markdown-mode rx color thingatpt noutline
outline icons lv inline imenu ht filenotify f s ewoc epg rfc6068
epg-config dash compile text-property-search comint ansi-osc ansi-color
ring cc-mode cc-fonts cc-guess cc-menus cc-cmds cc-styles cc-align
cc-engine cc-vars cc-defs corfu-echo corfu compat compat-30 cl-extra
help-mode use-package use-package-ensure use-package-delight
use-package-diminish use-package-bind-key bind-key easy-mmode
use-package-core corfu-autoloads compat-autoloads lsp-mode-autoloads
ht-autoloads f-autoloads info dash-autoloads lv-autoloads
markdown-mode-autoloads s-autoloads spinner-autoloads package browse-url
url url-proxy url-privacy url-expand url-methods url-history url-cookie
generate-lisp-file url-domsuf url-util mailcap url-handlers url-parse
auth-source cl-seq eieio eieio-core cl-macs password-cache json subr-x
map byte-opt gv bytecomp byte-compile url-vars cl-loaddefs cl-lib rmc
iso-transl tooltip cconv eldoc paren electric uniquify ediff-hook
vc-hooks lisp-float-type elisp-mode mwheel term/x-win x-win
term/common-win x-dnd tool-bar dnd fontset image regexp-opt fringe
tabulated-list replace newcomment text-mode lisp-mode prog-mode register
page tab-bar menu-bar rfn-eshadow isearch easymenu timer select
scroll-bar mouse jit-lock font-lock syntax font-core term/tty-colors
frame minibuffer nadvice seq simple cl-generic indonesian philippine
cham georgian utf-8-lang misc-lang vietnamese tibetan thai tai-viet lao
korean japanese eucjp-ms cp51932 hebrew greek romanian slovak czech
european ethiopic indian cyrillic chinese composite emoji-zwj charscript
charprop case-table epa-hook jka-cmpr-hook help abbrev obarray oclosure
cl-preloaded button loaddefs theme-loaddefs faces cus-face macroexp
files window text-properties overlay sha1 md5 base64 format env
code-pages mule custom widget keymap hashtable-print-readable backquote
threads dbusbind inotify lcms2 dynamic-setting system-font-setting
font-render-setting cairo move-toolbar gtk x-toolkit xinput2 x multi-tty
make-network-process emacs)

Memory information:
((conses 16 203184 12765)
  (symbols 48 23270 0)
  (strings 32 74270 2672)
  (string-bytes 1 2204500)
  (vectors 16 48780)
  (vector-slots 8 757848 20048)
  (floats 8 190 29)
  (intervals 56 799 0)
  (buffers 984 16))

[-- Attachment #2: init.el --]
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(setq user-emacs-directory "~/minimal/")

(add-to-list 'package-archives
             '("melpa" . "https://melpa.org/packages/"))
(require 'use-package)

(use-package lsp-mode
  :ensure t
  :commands (lsp lsp-deferred)
  :init
  (setq lsp-keymap-prefix "C-c l")  ;; Or 'C-l', 's-l'
  :config
  (setq lsp-completion-provider :none))

(use-package c-mode
  :ensure nil
  :hook (((c++-mode c-mode) . lsp-deferred)))

(use-package corfu
  :ensure t
  :custom
  (corfu-auto t)
  (corfu-auto-delay 0.2)
  (corfu-auto-prefix 1)
  (corfu-echo-documentation t)
  (corfu-min-width 20)
  :config
  (global-corfu-mode)
  (corfu-echo-mode))

(custom-set-variables
 ;; custom-set-variables was added by Custom.
 ;; If you edit it by hand, you could mess it up, so be careful.
 ;; Your init file should contain only one such instance.
 ;; If there is more than one, they won't work right.
 '(package-selected-packages '(use-package)))
(custom-set-faces
 ;; custom-set-faces was added by Custom.
 ;; If you edit it by hand, you could mess it up, so be careful.
 ;; Your init file should contain only one such instance.
 ;; If there is more than one, they won't work right.
 )

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#37 0x00007ffff5acac88 in __libc_start_call_main (main=main@entry=0x5555555868c0, argc=argc@entry=4, 
    argv=argv@entry=0x7fffffffe148) at ../sysdeps/nptl/libc_start_call_main.h:58
        self = <optimized out>
        result = <optimized out>
        unwind_buf = {cancel_jmp_buf = {{jmp_buf = {140737488347464, 8312541994804177299, 4, 0, 140737354125312, 
                93824995730904, 8312541994810468755, 8312519293894912403}, mask_was_saved = 0}}, priv = {pad = {
              0x0, 0x0, 0x4, 0x7fffffffe140}, data = {prev = 0x0, cleanup = 0x0, canceltype = 4}}}
        not_first_call = <optimized out>
#38 0x00007ffff5acad4c in __libc_start_main_impl (main=0x5555555868c0, argc=4, argv=0x7fffffffe148, 
    init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7fffffffe138)
    at ../csu/libc-start.c:360
No locals.
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