Bugzilla Bug 12757

I upgraded to gdm-2.4.0.12-r2 from gnome-base/gdm-2.4.0.11-r1... I dont really
see  what causes the problem.. I tried replacing all of the "customised" config
files with the defaults ones... didnt change anything...

I noticed the same when I upgraded to 2.4.0.12, and tracked the issue to having
sub-pixel rendering turned on in fonts.conf.

It also works here when I disable sub-pixel AA. Btw, I use Gtk/glib 2.2.0,
pango
1.2.0 with fontconfig 2.1-r1 and xft-2.0.1-r1.. Btw is it possible to disable
sub-pixel AA for a single app?

I use the exact same library versions as you (with freetype 2.1.3-r2 in
addition). I also find that Nautilus (2.0.8) crashes when I attempt to open a
window with sub-pixel rendering on (it renders the desktop fine).

I was having the exact same problem with GDM before the latests gtk/glib/pango
were released.

I also have the same problem with nautilus... I filed this bug on
bugzilla.gnome.org.. They called it "not gnome".

http://bugzilla.gnome.org/show_bug.cgi?id=102322

Downgrading to fontconfig 2.0-r4 has fixed this for me, and zooming in on a
screenshot confirms that sub-pixel rendering is indeed working.

This appears to be a bug in fontconfig-2.1 and up.

I get the same results with fontconfig 2.0-r3 -r4 and 2.1 -r0 -r1.... (None of
them works correctly)

Disable subpixel in /etc/fonts/fonts.conf , try the gnome2 fonts dialog to set
subpixeling with that.

Any word ?

I set subpixel rendering in the gnome2 font dialog, but when I take a
screenshot
and blow it up you can tell that it hasn't actually been enabled; only standard
antialiasing is being used.

1) seems the fonts.conf way of enabling subpixel rendering is faulty -> there
is no name 'rgba' ? i'm not quite sure how this all ties together.

2) My suggestion of enabling subpixel rendering in fonts dialog won't work for
gdm i think since it runs as its own user, but for users it should run fine. I
can with correct settings see subpixelrendering done in colors.

Can anyone confirm 2) and figure out what the correct way for setting it in
fonts.conf is 1) ?

ok, the crash disappears with gdmgreeter if i comment out the <test> block in 
the "subpixel" match block. something like this:

<!-- Enable sub-pixel rendering -->
   <match target="font">
      <!--
      <test qual="all" name="rgba">
         <const>unknown</const>
      </test>
      -->
      <edit name="rgba" mode="assign"><const>rgb</const></edit>
   </match>

it crashes if the <test> part is uncommented. i'm not sure if i understand
this XML at all, to be honest, but it seems to be part of the default 
configuration. redhat 7.3 doesn't have that test in its fontconfig default conf 
files.

foser, i can confirm 2. the settings in font properties set the user's own font rendering settings, and not the global ones.

with the test disabled (which doesnt seem to be correct allright), there is no
subpixel rendering in gdm at all afaics.

Altough in one of the fontconfig sample configs it is mentioned like that
(without the test block).

I got a core dump off gdmgreeter and the segfaults happens deep inside
fontconfig code.   And as luck would have it, a new fontconfig has been
committed to portage and fixes this problem. So, does the new fontconfig solve
the gdmgreeter crashing for you?   To me, the fonts look like they're using
sub-pixel rendering. Remember you have to edit /etc/fonts/local.conf and
uncomment the subpixel xml stanza.

just added 2.2.0-r2 which should include a local.conf without the test stuff.

please test so i can mark it stable and mark stable

fontconfig that is ;)

foser,

seems to be a problem with the cvs_bugfixes patch applying :

...
--------------------------
|Only in fontconfig: .cvsignore
|Only in fontconfig: CVS
|diff -ur fontconfig-2.2.0/ChangeLog fontconfig/ChangeLog
|--- fontconfig-2.2.0/ChangeLog  2003-04-17 19:43:04.000000000 +0200
|+++ fontconfig/ChangeLog  2003-05-14 18:29:07.000000000 +0200
--------------------------
No file to patch.  Skipping patch.
1 out of 1 hunk ignored
can't find file to patch at input line 156
Perhaps you used the wrong -p or --strip option?
The text leading up to this was:
--------------------------
|Only in fontconfig-2.2.0: Makefile.in
|Only in fontconfig-2.2.0: aclocal.m4
|Only in fontconfig: autogen.sh
|Only in fontconfig: config
|Only in fontconfig-2.2.0: config.guess
|Only in fontconfig-2.2.0: config.h.in
|Only in fontconfig-2.2.0: config.sub
...

yes :( duh i know, fixed patch is in.

i can confirm the new fontconfig doesn't crash gdm when that test stanza is
removed.

ok.. i'll go with that.

According to keithp, this problem is fixed in current fontconfig (2.3.0), maybe
older versions, so perhaps this workaround should be re-examined.