[cairo] What does it take to get a make check to pass with the xcb target, using CAIRO_REF_DIR?

[Lawrence D'Oliveiro]

On Mon, 11 Jul 2016 11:47:40 -0700, Bryce Harrington wrote:

> On Sun, Jul 10, 2016 at 11:18:28AM +1200, Lawrence D'Oliveiro wrote:
> 
>> There have been some changes in the rendering behaviour of
>> FreeType.  
> 
> Do you have more details?  That sounds like something that might
> account for a large share of image mismatches...

I can mention a personal example. A client was complaining that a
script of mine was not doing layout right. Yet when they sent me the
exact same fonts and control file, the output looked fine on my
machine. Finally, they set up an Ubuntu AWS instance, similar to their
production server, for me to try it on, and there I was able to
reproduce the problem.

Turned out the version of FreeType on my machine was slightly
older than their one, and there was a difference in the metrics being
returned for the same font.

The older FreeType version (2.5.2-something) remains in Debian Stable
8.x, but the newer version (2.6.2) was soon available in Debian
Unstable, and when I upgraded (this was back in October), things
became consistent again.