[tlbuild] Does texlive still require a modified icu?

[Peter Breitenlohner]

On Tue, 28 Oct 2014, Edd Barrett wrote:

> I've been prodding around in the texlive sources trying to figure out the
> following:
>
> Traditionally TL required a hacked version of ICU, is that still so? Can I
> use the system ICU for tex live 2013 and 2014 without problems?
>
> I'm looking at the patches in-tree and thinking I *can* use the system icu,
> but I want to be sure.

Hi Ed,

There were two kinds of modifications:

(1) one system (some BSD variant as far as I remember) could not resolve
external reference more than 16M away.  Thus we (Jonathan Kew and myself)
decided that we can leave out some of the data, thus reducing the size of
icudt49l.dat from about 17M to 12M in 2012, and more recently icudt54l.dat
from 24M to 16M.

Until Mar 2013 xetex did require a modified version of the ICU layout
library, but these days this is handled by (unmodofied) harfbuzz.  For the
last years it was thus possible to use a system version as shown by
'configure --help'.  The only remaining patches address build problems for
various systems and are irrelevant when using a system version .

Regards
Peter