[Pkg-emacsen-addons] Bug#969103: elpa-flycheck: causes leak in GNU Emacs 27.1

[Lev Lamberov]

Package: elpa-flycheck
Severity: critical
X-Debbugs-Cc: none, Lev Lamberov <dogsleg at debian.org>
User: debian-emacsen at lists.debian.org
Usertags: emacs27

Dear Maintainer,

elpa-flycheck causes leak in GNU Emacs 27.1 from the Debian archive
(1:27.1+1-1, currently from experimental).

Excerpt from debug log:

Debugger entered--Lisp error: (error "Lisp nesting exceeds ‘max-lisp-eval-depth’")
  cl-subseq([("File" 6) ("Line" 5 flycheck-error-list-entry-< :right-align t) ("Col" 3 nil :right-align t) ("Level" 8 flycheck-error-list-entry-level-<) ("ID" 6 t) (#("Message (Checker)" 9 16 (face flycheck-error-list-checker-name)) 0 t)] 0 -1)
  seq-subseq([("File" 6) ("Line" 5 flycheck-error-list-entry-< :right-align t) ("Col" 3 nil :right-align t) ("Level" 8 flycheck-error-list-entry-level-<) ("ID" 6 t) (#("Message (Checker)" 9 16 (face flycheck-error-list-checker-name)) 0 t)] 0 -1)
  cl-subseq([("File" 6) ("Line" 5 flycheck-error-list-entry-< :right-align t) ("Col" 3 nil :right-align t) ("Level" 8 flycheck-error-list-entry-level-<) ("ID" 6 t) (#("Message (Checker)" 9 16 (face flycheck-error-list-checker-name)) 0 t)] 0 -1)
  seq-subseq([("File" 6) ("Line" 5 flycheck-error-list-entry-< :right-align t) ("Col" 3 nil :right-align t) ("Level" 8 flycheck-error-list-entry-level-<) ("ID" 6 t) (#("Message (Checker)" 9 16 (face flycheck-error-list-checker-name)) 0 t)] 0 -1)
  cl-subseq([("File" 6) ("Line" 5 flycheck-error-list-entry-< :right-align t) ("Col" 3 nil :right-align t) ("Level" 8 flycheck-error-list-entry-level-<) ("ID" 6 t) (#("Message (Checker)" 9 16 (face flycheck-error-list-checker-name)) 0 t)] 0 -1)
  seq-subseq([("File" 6) ("Line" 5 flycheck-error-list-entry-< :right-align t) ("Col" 3 nil :right-align t) ("Level" 8 flycheck-error-list-entry-level-<) ("ID" 6 t) (#("Message (Checker)" 9 16 (face flycheck-error-list-checker-name)) 0 t)] 0 -1)
  cl-subseq([("File" 6) ("Line" 5 flycheck-error-list-entry-< :right-align t) ("Col" 3 nil :right-align t) ("Level" 8 flycheck-error-list-entry-level-<) ("ID" 6 t) (#("Message (Checker)" 9 16 (face flycheck-error-list-checker-name)) 0 t)] 0 -1)
  seq-subseq([("File" 6) ("Line" 5 flycheck-error-list-entry-< :right-align t) ("Col" 3 nil :right-align t) ("Level" 8 flycheck-error-list-entry-level-<) ("ID" 6 t) (#("Message (Checker)" 9 16 (face flycheck-error-list-checker-name)) 0 t)] 0 -1)

[..]

  byte-code("\302\303\304\10\305\306#\11#\207" [flycheck-error-list-format flycheck-error-list-padding seq-reduce #f(compiled-function (offset fmt) #<bytecode 0x157851333cdd>) seq-subseq 0 -1] 6)
  (defconst flycheck--error-list-msg-offset (byte-code "\302\303\304\10\305\306#\11#\207" [flycheck-error-list-format flycheck-error-list-padding seq-reduce #f(compiled-function (offset fmt) #<bytecode 0x157851333cdd>) seq-subseq 0 -1] 6) ("/usr/share/emacs/site-lisp/elpa/flycheck-32snapsho..." . 171725))
  autoload-do-load((autoload "flycheck" "Minor mode for on-the-fly syntax checking.\n\nWhen c..." t nil) flycheck-mode)
  desktop-load-file(flycheck-mode)

With regards,
Lev

-- System Information:
Debian Release: bullseye/sid
  APT prefers testing
  APT policy: (990, 'testing'), (500, 'unstable'), (1, 'experimental')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 5.7.0-2-amd64 (SMP w/4 CPU threads)
Kernel taint flags: TAINT_PROPRIETARY_MODULE, TAINT_WARN, TAINT_OOT_MODULE, TAINT_UNSIGNED_MODULE
Locale: LANG=ru_RU.UTF-8, LC_CTYPE=ru_RU.UTF-8 (charmap=UTF-8), LANGUAGE not set
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled