bug#40370: 24.5; fail to display svg file containing accented characters

[Didier Kryn]

When editing an SVG drawing, hitting ctrl-C+ctrl-C toggles display mode
between source text and graphical. This works fine as long as the source
does not contain accented characters. When the source contains accented
characters, the graphical display is the same as for an erroneous SVG
file, except right after the file has been read or written. In the
example below, it is enough to replace the 'é' of "Bézier" by an 'e' to
not see this effect:


<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<svg version="1.1" xmlns="http://www.w3.org/2000/svg";
     width="100mm" height="100mm" viewBox="0 0 100 100"
     preserveAspectRatio="meet"
     font-style="normal" stroke="black" fill="black" stroke-width="0.5">

  <rect x="0.25" y="0.25" width="99.5" height="99.5" fill="none"
    stroke-dasharray="3 3"/>

  <g transform="matrix(20,0,0,20,50,40)" stroke-width="0.1" fill="none">
    <path d="M0,1  c 0.5519, 0  1,-0.4481  1,-1" stroke="red"/>
    <path d="M1,0  c 0,-0.5519  -0.4481,-1 -1,-1" stroke="blue"/>
    <path d="M0,-1 c -0.5519, 0 -1,0.4481  -1, 1" stroke="yellow"/>
    <path d="M-1,0 c 0,0.5519   0.4481, 1   1, 1" stroke="magenta"/>
  </g>

  <g text-anchor="middle" font-size="7" stroke="none">
    <text x="50" y="80">Approximation of a circle</text>
    <text x="50" y="88">by four cubic Bézier curves</text>
  </g>

</svg>


In GNU Emacs 24.5.1 (x86_64-pc-linux-gnu, GTK+ Version 3.22.11)
of 2017-09-12 on hullmann, modified by Debian
Windowing system distributor `The X.Org Foundation', version 11.0.11902000
System Description: Devuan GNU/Linux 2.1 (ascii)

Configured using:
`configure --build x86_64-linux-gnu --prefix=3D/usr
--sharedstatedir=3D/var/lib --libexecdir=3D/usr/lib
--localstatedir=3D/var/lib --infodir=3D/usr/share/info
--mandir=3D/usr/share/man --with-pop=3Dyes
--enable-locallisppath=3D/etc/emacs24:/etc/emacs:/usr/local/share/emacs/24=
.5/site-lisp:/usr/local/share/emacs/site-lisp:/usr/share/emacs/24.5/site-li= 

sp:/usr/share/emacs/site-lisp
--without-gnutls --build x86_64-linux-gnu --prefix=3D/usr
--sharedstatedir=3D/var/lib --libexecdir=3D/usr/lib
--localstatedir=3D/var/lib --infodir=3D/usr/share/info
--mandir=3D/usr/share/man --with-pop=3Dyes
--enable-locallisppath=3D/etc/emacs24:/etc/emacs:/usr/local/share/emacs/24=
.5/site-lisp:/usr/local/share/emacs/site-lisp:/usr/share/emacs/24.5/site-li= 

sp:/usr/share/emacs/site-lisp
--without-gnutls --with-x=3Dyes --with-x-toolkit=3Dgtk3
--with-toolkit-scroll-bars 'CFLAGS=3D-g -O2
-fdebug-prefix-map=3D/build/emacs24-24.5+1=3D. -fstack-protector-strong
-Wformat -Werror=3Dformat-security -Wall -fno-PIE' 'CPPFLAGS=3D-Wdate-time
-D_FORTIFY_SOURCE=3D2' 'LDFLAGS=3D-Wl,-z,relro -no-pie''

Important settings:
value of $LANG: fr_FR.utf8
locale-coding-system: utf-8-unix

Major mode: nXML

Minor modes in effect:
image-minor-mode: t
tooltip-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:
Loading /var/cache/dictionaries-common/emacsen-ispell-dicts.el 
(source)...d=
one
Loading /etc/emacs/site-start.d/50dictionaries-common.el (source)...done
Loading /etc/emacs/site-start.d/50gnats-user.el (source)...done
Loading /etc/emacs/site-start.d/50verbiste-el.el (source)...done
For information about GNU Emacs and the GNU system, type C-h C-a.
Type C-c C-c to view the image as text.
Using vacuous schema
Type C-c C-c to view the image as an image.
Error during redisplay: (jit-lock-function 1) signaled 
(args-out-of-range 1=
56)
No document element

Load-path shadows:
/usr/share/emacs/24.5/site-lisp/debian-startup hides 
/usr/share/emacs/site-=
lisp/debian-startup

Features:
(shadow sort gnus-util mail-extr emacsbug message format-spec rfc822 mml
mml-sec mm-decode mm-bodies mm-encode mail-parse rfc2231 mailabbrev
gmm-utils mailheader sendmail rfc2047 rfc2045 ietf-drums mm-util
help-fns mail-prsvr mail-utils nxml-uchnm rng-xsd xsd-regexp rng-cmpct
rng-nxml rng-valid rng-loc rng-uri rng-parse nxml-parse rng-match rng-dt
rng-util rng-pttrn nxml-ns nxml-mode nxml-outln nxml-rap nxml-util
nxml-glyph nxml-enc xmltok image-mode easymenu edmacro kmacro
cl-loaddefs cl-lib leuven-theme time-date tooltip electric uniquify
ediff-hook vc-hooks lisp-float-type mwheel x-win x-dnd tool-bar dnd
fontset image regexp-opt fringe tabulated-list newcomment lisp-mode
prog-mode register page menu-bar rfn-eshadow timer select scroll-bar
mouse jit-lock font-lock syntax facemenu font-core frame cham georgian
utf-8-lang misc-lang vietnamese tibetan thai tai-viet lao korean
japanese hebrew greek romanian slovak czech european ethiopic indian
cyrillic chinese case-table epa-hook jka-cmpr-hook help simple abbrev
minibuffer 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 make-network-process
dbusbind gfilenotify dynamic-setting system-font-setting
font-render-setting move-toolbar gtk x-toolkit x multi-tty emacs)

Memory information:
((conses 16 105051 6555)
(symbols 48 20328 0)
(miscs 40 107 132)
(strings 32 16527 3995)
(string-bytes 1 443692)
(vectors 16 11674)
(vector-slots 8 410967 5079)
(floats 8 130 332)
(intervals 56 893 10)
(buffers 960 14))