Subject: bug#77918: 31.0.50; Warnings about missing 'lexical-binding' cookie in *Async-native-compile-log*

From: Roi Martin <[email-masked]>
Date: Sat, 19 Apr 2025 10:41:35 +0200

Several warnings about missing 'lexical-binding' cookie show up in
*Async-native-compile-log*.  They seem to show up when a feature that
has not been compiled yet is used and needs to be compiled.  The issue
is reproducible by just running 'emacs -Q'.  You can find some of the
warnings below.

  Warning (files): Missing ‘lexical-binding’ cookie in "/tmp/emacs-async-comp-dired-aux-xXuqdt.el".
  You can add one with ‘M-x elisp-enable-lexical-binding RET’.
  See ‘(elisp)Selecting Lisp Dialect’ and ‘(elisp)Converting to Lexical Binding’
  for more information.
  Compiling /home/n/src/emacs/lisp/dired-aux.el...
  Compilation finished.
  Warning (files): Missing ‘lexical-binding’ cookie in "/tmp/emacs-async-comp-shell-rZsYYK.el".
  You can add one with ‘M-x elisp-enable-lexical-binding RET’.
  See ‘(elisp)Selecting Lisp Dialect’ and ‘(elisp)Converting to Lexical Binding’
  for more information.
  Compiling /home/n/src/emacs/lisp/shell.el...
  Warning (files): Missing ‘lexical-binding’ cookie in "/tmp/emacs-async-comp-pcomplete-lO4nJm.el".
  You can add one with ‘M-x elisp-enable-lexical-binding RET’.
  See ‘(elisp)Selecting Lisp Dialect’ and ‘(elisp)Converting to Lexical Binding’
  for more information.
  Compiling /home/n/src/emacs/lisp/pcomplete.el...
  Warning (files): Missing ‘lexical-binding’ cookie in "/tmp/emacs-async-comp-files-x-oLXnPa.el".
  You can add one with ‘M-x elisp-enable-lexical-binding RET’.
  See ‘(elisp)Selecting Lisp Dialect’ and ‘(elisp)Converting to Lexical Binding’
  for more information.
  Compiling /home/n/src/emacs/lisp/files-x.el...
  Compilation finished.
  Warning (files): Missing ‘lexical-binding’ cookie in "/tmp/emacs-async-comp-rfc2047-XugClb.el".
  You can add one with ‘M-x elisp-enable-lexical-binding RET’.
  See ‘(elisp)Selecting Lisp Dialect’ and ‘(elisp)Converting to Lexical Binding’
  for more information.
  Compiling /home/n/src/emacs/lisp/mail/rfc2047.el...
  Compilation finished.

What follows is one of the .el files that produced the warning
(emacs-async-comp-icomplete-tWY9i1.el).  Note that I elided the
native-comp-eln-load-path and load-path values to shorten the report.

  (require 'comp)(setq comp-async-compilation t warning-fill-column most-positive-fixnum)(setq comp-file-preloaded-p 'nil native-comp-verbose '0 native-comp-eln-load-path '(...) load-path '(...) byte-compile-warnings 't)nil(message "Compiling %s..." "/home/n/src/emacs/lisp/icomplete.el")(comp--native-compile "/home/n/src/emacs/lisp/icomplete.el" t)

In GNU Emacs 31.0.50 (build 4, x86_64-pc-linux-gnu, GTK+ Version
 3.24.43, cairo version 1.18.2) of 2025-04-19 built on wopr
Repository revision: 9ea9c5a73e004903ca1c6e15cf5797458315ad9a
Repository branch: master
Windowing system distributor 'The X.Org Foundation', version 11.0.12401006
System Description: Fedora Linux 41 (Workstation Edition)

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

Important settings:
  value of $LC_MONETARY: en_IE.UTF-8
  value of $LC_NUMERIC: en_IE.UTF-8
  value of $LC_TIME: en_IE.UTF-8
  value of $LANG: en_US.UTF-8
  value of $XMODIFIERS: @im=ibus
  locale-coding-system: utf-8-unix

Major mode: elisp-compile

Minor modes in effect:
  icomplete-mode: t
  fido-mode: t
  tooltip-mode: t
  global-eldoc-mode: t
  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
  font-lock-mode: t
  blink-cursor-mode: t
  minibuffer-regexp-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:
None found.

Features:
(help-mode pp shadow sort mail-extr emacsbug lisp-mnt message mailcap
yank-media puny rfc822 mml mml-sec password-cache epa derived epg
rfc6068 epg-config gnus-util time-date mm-decode mm-bodies mm-encode
mail-parse rfc2231 mailabbrev gmm-utils mailheader sendmail rfc2047
rfc2045 ietf-drums mm-util mail-prsvr mail-utils display-line-numbers
files-x shell pcomplete compile text-property-search comint subr-x
ansi-osc ansi-color ring dired-aux dired dired-loaddefs comp-run
bytecomp byte-compile comp-common rx icomplete 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 touch-screen 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 dynamic-setting system-font-setting
font-render-setting cairo gtk x-toolkit xinput2 x multi-tty move-toolbar
make-network-process tty-child-frames native-compile emacs)

Memory information:
((conses 16 171289 28956) (symbols 48 7497 4) (strings 32 26333 2931)
 (string-bytes 1 757901) (vectors 16 14367)
 (vector-slots 8 182883 43794) (floats 8 35 1262)
 (intervals 56 5930 1736) (buffers 992 16))