Subject: bug#42655: 27.1; iconify-frame on a Lucid build may stuck the frame

From: Tino Calancha <[email-masked]>
Date: Sat, 01 Aug 2020 20:46:03 +0200

X-Debbugs-Cc: Stefan Monnier <[email-masked]>, Paul Eggert <[email-masked]>, <[email-masked]>
Severity: wishlist

* To reproduce

-------------------------------------------------------------------------------
In a GUI session, with Emacs built with Lucid toolkit in a Linux machine,
do:
emacs -Q
C-z
;; select again the window displaying the Emacs GUI
-------------------------------------------------------------------------------

- You cannot insert characters in the *scratch* buffer.
- Normal movement, for intance, `C-n' or `C-f' doesn't work.

trick: `M-x' recovers the frame.

Unfortunately, when I start Emacs without the `-Q' flag, then this trick
doesn't work for me: the frame keeps unresponsive forever, and I have 2 choices:
1) Restart Emacs session (unaceptable for users).
2) Get 'blindly' (ie, without echo area feedback) a new frame:
C-x 5 b foo RET

* Expected behavior:

After `C-z' and select again the Emacs GUI you have a fully responsive
frame displaying the *scratch* buffer: you can insert characters and/or
move the cursor anywhere.

* Workaround:
Install gtk3-devel and build Emacs with GTK3 toolkit

In GNU Emacs 27.1 (build 1, x86_64-pc-linux-gnu, X toolkit, Xaw3d scroll bars)
 of 2020-08-01 built on calancha-pc.dy.bbexcite.jp
Repository revision: f54ddb0198640e38c1d34bf6031ff5117c117c85
Repository branch: emacs-27
Windowing system distributor 'The X.Org Foundation', version 11.0.12004000
System Description: Debian GNU/Linux 10 (buster)

Recent messages:
For information about GNU Emacs and the GNU system, type C-h C-a.
Quit [2 times]
funcall-interactively: End of buffer
scroll-up-command: End of buffer
Configured using:
 'configure --with-x-toolkit=lucid'

Configured features:
XAW3D XPM JPEG TIFF GIF PNG RSVG SOUND GPM DBUS GSETTINGS GLIB NOTIFY
INOTIFY ACL LIBSELINUX GNUTLS LIBXML2 FREETYPE HARFBUZZ M17N_FLT LIBOTF
XFT ZLIB TOOLKIT_SCROLL_BARS LUCID X11 XDBE XIM MODULES THREADS
LIBSYSTEMD PDUMPER LCMS2 GMP

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

Major mode: Lisp Interaction

Minor modes in effect:
  tooltip-mode: t
  global-eldoc-mode: t
  eldoc-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
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t

Load-path shadows:
None found.

Features:
(shadow sort mail-extr emacsbug message rmc puny dired dired-loaddefs
format-spec rfc822 mml easymenu mml-sec password-cache epa derived epg
epg-config gnus-util rmail rmail-loaddefs text-property-search time-date
subr-x seq byte-opt gv bytecomp byte-compile cconv mm-decode mm-bodies
mm-encode mail-parse rfc2231 mailabbrev gmm-utils mailheader cl-loaddefs
cl-lib sendmail rfc2047 rfc2045 ietf-drums mm-util mail-prsvr mail-utils
tooltip eldoc electric uniquify ediff-hook vc-hooks lisp-float-type
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 elisp-mode
lisp-mode prog-mode register page tab-bar menu-bar rfn-eshadow isearch
timer select scroll-bar mouse jit-lock font-lock syntax facemenu
font-core term/tty-colors frame minibuffer cl-generic 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 charscript charprop
case-table epa-hook jka-cmpr-hook help simple abbrev obarray
cl-preloaded nadvice loaddefs button faces cus-face macroexp files
text-properties overlay sha1 md5 base64 format env code-pages mule
custom widget hashtable-print-readable backquote threads dbusbind
inotify lcms2 dynamic-setting system-font-setting font-render-setting
x-toolkit x multi-tty make-network-process emacs)

Memory information:
((conses 16 44708 6402)
 (symbols 48 5984 1)
 (strings 32 16489 1646)
 (string-bytes 1 525028)
 (vectors 16 9267)
 (vector-slots 8 124678 11056)
 (floats 8 22 43)
 (intervals 56 212 0)
 (buffers 1000 11))