Bug#239448: libxft2: Fails to render fonts, making GTK+ 2 and related system unusable.

[Scott Robinson <scott@tranzoa.com>]

Package: libxft2
Version: 2.1.2-6
Severity: grave
Tags: sid
Justification: renders package unusable

The latest update of libxft2 has made my system totally unusable. It fails
to render fonts properly such that my desktop environment appears strangely
blank. Menus and related items are sized improperly. The following link
given an example:

http://tranzoa.net/~scott/no-fonts.jpeg 

I tracked the problem down to xft via mozilla-firebird. Unlike other gtk+2
applications, it was crashing (floating point exception) instead of
rendering blank. GDB gave me the following backtrace:

#0  0x4201db67 in nsFontMetricsXft::CacheFontMetrics() ()
   from /usr/lib/mozilla-firefox/components/libgfx_gtk.so
#1  0x4201da22 in nsFontMetricsXft::RealizeFont() ()
   from /usr/lib/mozilla-firefox/components/libgfx_gtk.so
#2  0x00000061 in ?? ()
#3  0x42037330 in nsICharRepresentable::GetIID()::iid ()
   from /usr/lib/mozilla-firefox/components/libgfx_gtk.so
#4  0x42048730 in gXftFontLoad ()
   from /usr/lib/mozilla-firefox/components/libgfx_gtk.so
#5  0x4203ea18 in ?? () from /usr/lib/mozilla-firefox/components/libgfx_gtk.so
#6  0xbfffda24 in ?? ()
#7  0xbfffdae8 in ?? ()
#8  0x4201cabe in nsFontMetricsXft::Init(nsFont const&, nsIAtom*, nsIDeviceContext*) () from /usr/lib/mozilla-firefox/components/libgfx_gtk.so

This pointed me in the thought that the newly updated package wasn't reading
my cached font metrics properly.

I have temporarily gained a working system creating a stub .xsession with the line:

export GDK_USE_XFT=0

The full .xsession (for anyone else experiencing this problem and wanting a working system):

#!/bin/sh

export GDK_USE_XFT=0

if [ -x /usr/bin/x-session-manager ]; then
  STARTUP=x-session-manager
elif [ -x /usr/bin/x-window-manager ]; then
  STARTUP=x-window-manager
elif [ -x /usr/bin/x-terminal-emulator ]; then
  STARTUP=x-terminal-emulator
fi

exec $STARTUP

My next hunch is to regenerate my font metrics. If this is the source of the
problem, I recommend forcing this to occur on update and releasing a new
package that handles that.

This has been a disaster experience is terms of I carefully checked
apt-listbugs for problems like this.

-- System Information:
Debian Release: testing/unstable
  APT prefers unstable
  APT policy: (500, 'unstable')
Architecture: i386 (i686)
Kernel: Linux 2.6.4
Locale: LANG=C, LC_CTYPE=C

Versions of packages libxft2 depends on:
ii  libc6                       2.3.2.ds1-11 GNU C Library: Shared libraries an
ii  libfontconfig1              2.2.2-1      generic font configuration library
ii  libfreetype6                2.1.7-2      FreeType 2 font engine, shared lib
ii  libx11-6                    4.3.0-7      X Window System protocol client li
ii  libxrender1                 0.8.3-7      X Rendering Extension client libra
ii  xlibs                       4.3.0-7      X Window System client libraries m
ii  zlib1g                      1:1.2.1-5    compression library - runtime

-- no debconf information