Subject: bug#24088: emacs 25.0.95; display problems in terminal emulator after unicode wheelcair symbol

From: Gregor Zattler <[email-masked]>
Date: Wed, 27 Jul 2016 18:32:11 +0200

Dear Emacs developers,

with this (see below) recently build emacs -Q -nw in an xterm /
urxvt (this does not happen in a graphical frame) enter this
Text:

Zwangsräumung von HG♿M99

The symbol between "HG" and "M99" is the unicode wheelchair symbol.

With point at the wheelchair symbol hit C-f: The cursor moves not to the
"M" but to the left "9".  This gives problems in the rest of the line
when one for instance swaps characters with C-t.  When doing so a few
times it's hard to tell if it's a display problem or if the letters are
swapped around.

The problem is also visible at the line between windows (see attached
screen shot).  This happens when hitting C-l.

Is this an emacs bug, a terminal emulators bug or a bug of the font used?

Thanks for looking into this, Gregor

P.S.: Totally unrelated to this emacs problem: HG is a person who needs to use
a wheelchair, M99 is a shop in Berlin/Kreuzberg HG runs and in which he
also lives.  His forcefull eviction is scheduled for 9th of August.

In GNU Emacs 25.0.95.1 (x86_64-pc-linux-gnu, GTK+ Version 3.20.6)
 of 2016-07-24 built on len
Repository revision: 0e646c73f57fc50de36ef659ead9a94968f8cba7
System Description:	Debian GNU/Linux testing (stretch)

Configured using:
 'configure --prefix=/usr/local/stow/emacs-snapshot
 --with-file-notification=inotify --enable-checking
 --without-toolkit-scroll-bars --with-x-toolkit=gtk3'

Configured features:
XPM JPEG TIFF GIF PNG RSVG IMAGEMAGICK SOUND GPM DBUS GCONF GSETTINGS
NOTIFY ACL LIBSELINUX GNUTLS LIBXML2 FREETYPE M17N_FLT LIBOTF XFT ZLIB
GTK3 X11

Important settings:
  value of $LC_COLLATE: de_DE.utf8
  value of $LC_CTYPE: de_DE.utf8
  value of $LC_MESSAGES: POSIX
  value of $LC_MONETARY: de_DE.utf8
  value of $LC_NUMERIC: de_DE.utf8
  value of $LC_TIME: de_DE.utf8
  value of $LANG: de_DE.utf8
  locale-coding-system: utf-8-unix

Major mode: Lisp Interaction

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

Recent messages:
For information about GNU Emacs and the GNU system, type C-h C-a.
kill-line: End of buffer [2 times]
Mark set [2 times]
Undo! [26 times]
scroll-down-command: Beginning of buffer [5 times]
Mark set [2 times]
Type C-x 1 to delete the help window.
next-line: End of buffer
Making completion list...

Load-path shadows:
None found.

Features:
(shadow sort mail-extr emacsbug message dired format-spec rfc822 mml
mml-sec password-cache epg epg-config 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 cl-extra
help-fns help-mode easymenu cl-loaddefs pcase cl-lib term/xterm xterm
time-date mule-util tooltip eldoc electric uniquify ediff-hook vc-hooks
lisp-float-type mwheel x-win term/common-win x-dnd tool-bar dnd fontset
image regexp-opt fringe tabulated-list newcomment elisp-mode lisp-mode
prog-mode register page menu-bar rfn-eshadow timer select scroll-bar
mouse jit-lock font-lock syntax facemenu font-core frame 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 charscript case-table epa-hook
jka-cmpr-hook help simple abbrev minibuffer 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 dbusbind inotify dynamic-setting
system-font-setting font-render-setting move-toolbar gtk x-toolkit x
multi-tty make-network-process emacs)

Memory information:
((conses 16 93560 5294)
 (symbols 48 20054 0)
 (miscs 40 51 171)
 (strings 32 15184 4315)
 (string-bytes 1 431177)
 (vectors 16 9893)
 (vector-slots 8 387568 16181)
 (floats 8 171 814)
 (intervals 56 409 13)
 (buffers 976 22)
 (heap 1024 24251 706))