Built Mapnik on Fedora(https://gist.github.com/3427021) and seeing a curious RTL visual test failure that likely has to do with ICU version. This is important because the main OSM server runs Fedora I think.
Visual text rendering summary: Failed: 183 different pixels:
yum info libicu gives:
yum info libicu
Name : libicu
Arch : x86_64
Version : 4.2.1
Release : 9.9.amzn1
Size : 19 M
Repo : installed
From repo : amzn-main
Summary : International Components for Unicode - libraries
URL : http://www.icu-project.org/
License : MIT and UCD and Public Domain
Description : The International Components for Unicode (ICU) libraries provide
: robust and full-featured Unicode services on a wide variety of
: platforms. ICU supports the most current version of the Unicode
: standard, and they provide support for supplementary Unicode
: characters (needed for GB 18030 repertoire support).
: As computing environments become more heterogeneous, software
: portability becomes more important. ICU lets you produce the same
: results across all the various platforms you support, without
: sacrificing performance. It offers great flexibility to extend and
: customize the supplied services.
This might happen when the "rtl" property in string_info is incorrectly initalized.
The code depends on ICU version, but your version should be recent enough.
You can try adding debug output here:
This problem is almost certainly fixed by the RTL-aware rewrite of the line breaking code.