Subject: bug#23291: closed (Re: bug#23291: Workaround for "25.0.92; Inserting unicode in buffer requiring a different font slows down Emacs")

From: [email-masked] (GNU bug Tracking System)
Date: Fri, 15 Apr 2016 14:18:02 +0000

Your bug report

#23291: 25.0.92; Inserting unicode in buffer requiring a different font slows down Emacs

which was filed against the emacs package, has been closed.

The explanation is attached below, along with your original report.
If you require more details, please reply to [email-masked].

-- 
23291: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=23291
GNU Bug Tracking System
Contact [email-masked] with problems

Subject: Re: bug#23291: Workaround for "25.0.92; Inserting unicode in buffer requiring a different font slows down Emacs"
From: Eli Zaretskii <[email-masked]>
To: Philippe Crama <[email-masked]>
Cc: [email-masked]
Date: Fri, 15 Apr 2016 17:16:36 +0300
List-Id: <debbugs-submit.debbugs.gnu.org>

> Date: Fri, 15 Apr 2016 15:17:16 +0200
> From: Philippe Crama <[email-masked]>
> 
> > Try installing Symbola, that's what Emacs uses on my system for that
> > character.
> 
> 1. downloaded Symbola from http://users.teilar.gr/~g1951d/
> 2. added this code to my .emacs.d/init.el file:
> (let ((unicode-fallback "Symbola"))
>   (when (x-list-fonts unicode-fallback)
>     (set-fontset-font "fontset-default"
>                       'unicode
>                       (font-spec :name unicode-fallback))))

Did you really need that addition?  Emacs 25 should use Symbola by
default (if available) for the Unicode block of characters that
includes u+2467 CIRCLED DIGIT EIGHT.  Perhaps you customized
fontset-default to countermand that?

> And my problem was solved.  Now the font used for CIRCLED DIGIT EIGHT
> is -outline-Symbola-normal-normal-normal-serif-13-*-*-*-p-*-iso8859-1
> 
> Thanks, Eli!

Thanks, I'm closing this bug.

Subject: 25.0.92; Inserting unicode in buffer requiring a different font slows down Emacs
From: "Philippe Crama" <[email-masked]>
To: [email-masked]
Date: Thu, 14 Apr 2016 21:28:55 +0200
List-Id: <debbugs-submit.debbugs.gnu.org>

1. Go to the *scratch* buffer or create a new buffer in fundamental mode
2. Observe that Emacs is quite responsive when typing random ASCII
characters
3. Insert (C-x 8 RET) a CIRCLED DIGIT EIGHT into the buffer
4. Continue typing: the buffer update is slower than before
5. Switch to another buffer and observe that Emacs is still as
responsive there as in step 2 once the slow buffer switch
happened.

Extra info:

1. This issue is
- NOT in Emacs 24.5 (GNU Emacs 24.5.1 (i686-pc-mingw32) of 2015-04-11
on LEG570 downloaded from http://gnu.xl-mirror.nl/emacs/windows/
- already in emacs-25.0.90-i686-w64-mingw32 (dowloaded
from the same http://alpha.gnu.org/gnu/emacs/windows/)

2. Characters from the ISO-8859-1 set (e.g. LATIN SMALL LETTER E WITH
ACUTE=C-x 8 ' e) do not have this problem.  Upon consideration, it's
maybe a question of font: this issue doesn’t happen for “RIGHTWARDS ARROW”
(C-x 8 a >).  C-u x = reports:
position: 125 of 144 (86%), column: 54
character: → (displayed as →) (codepoint 8594, #o20622, #x2192)
preferred charset: unicode (Unicode (ISO10646))
code point in charset: 0x2192
script: symbol
syntax: .                which means: punctuation
category: .:Base, c:Chinese, h:Korean, j:Japanese
to input: type "C-x 8 RET 2192" or "C-x 8 RET RIGHTWARDS ARROW"
buffer code: #xE2 #x86 #x92
file code: not encodable by coding system undecided-unix
display: by this font (glyph code)
uniscribe:-outline-Input-normal-normal-normal-mono-13-*-*-*-c-*-iso8859-1 (#x21E)

Character code properties: customize what to show
name: RIGHTWARDS ARROW
old-name: RIGHT ARROW
general-category: Sm (Symbol, Math)
decomposition: (8594) ('→')

There are text properties here:
fontified            t

3. In all versions I tested for this report, C-u x = reports the same
information for CIRCLED DIGIT EIGHT (I've replaced the troublesome
unicode character by `(8)'):
character: (8) (displayed as (8)) (codepoint 9319, #o22147, #x2467)
preferred charset: unicode (Unicode (ISO10646))
code point in charset: 0x2467
script: symbol
syntax: _         which means: symbol
category: .:Base, c:Chinese, h:Korean, j:Japanese
to input: type "C-x 8 RET 2467" or "C-x 8 RET CIRCLED DIGIT EIGHT"
buffer code: #xE2 #x91 #xA7
file code: #xE2 #x91 #xA7 (encoded by coding system utf-8-dos)
display: by this font (glyph code)
uniscribe:-outline-BatangChe-normal-normal-normal-mono-13-*-*-*-c-*-gb2312.1980-0 (#xF62)

Character code properties: customize what to show
name: CIRCLED DIGIT EIGHT
general-category: No (Number, Other)
decomposition: (circle 56) (circle '8')

In GNU Emacs 25.0.92.1 (i686-w64-mingw32) of 2016-03-21 built on LAPHROAIG

Windowing system distributor 'Microsoft Corp.', version 6.1.7601

Configured using:
'configure --host=i686-w64-mingw32 --without-dbus
--without-compress-install CFLAGS=-static'

Configured features:
XPM JPEG TIFF GIF PNG RSVG SOUND NOTIFY ACL GNUTLS LIBXML2 ZLIB
TOOLKIT_SCROLL_BARS

Important settings:
value of $LANG: en_US.UTF-8
locale-coding-system: cp1252

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
blink-cursor-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.
Making completion list... [3 times]

Load-path shadows:
None found.

Features:
(shadow sort mail-extr emacsbug message dired format-spec rfc822 mml
mml-sec 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 help-fns help-mode easymenu cl-loaddefs pcase
cl-lib mail-prsvr mail-utils iso-transl time-date mule-util tooltip
eldoc electric uniquify ediff-hook vc-hooks lisp-float-type mwheel
dos-w32 ls-lisp disp-table w32-win w32-vars term/common-win 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 w32notify w32 multi-tty
make-network-process emacs)
Memory information:
((conses 8 173134 14084)
(symbols 32 30311 0)
(miscs 32 43 119)
(strings 16 66961 7694)
(string-bytes 1 1488651)
(vectors 8 13576)
(vector-slots 4 563074 23106)
(floats 8 164 59)
(intervals 28 555 1222)
(buffers 520 12))