[webkit-gtk] Font regression

[Ochtman, Dirkjan]

We're trying to upgrade our webkit fork (which runs on Linux) from approximately 2011-11-02 to 2013-03-25. In doing so, we've run into a pretty bad font regression, as can be seen in this screen shot:

http://dirkjan.ochtman.nl/files/font-regression.png

(The upper two lines come from the old version, the lower two lines from the newer version.)

Despite many hours of research so far, we've been unable to come up with reliable ways to pin this on some particular piece of code. It seems like this kind of thing could be in either webkit, freetype, fontconfig, cairo or some interaction between any of these. Our two stacks are:

WebKit 2011-11-02, freetype 2.4.4, cairo 1.11.3, fontconfig 2.8.0
WebKit 2013-03-25, freetype 2.4.11, cairo 1.12.14, fontconfig 2.8.0

We also tried to upgrade freetype and cairo to much more recent versions, but that hasn't helped so far.

If someone is able to point us in any kind of direction, that would be very welcome.

Cheers,

Dirkjan