xetex? ( >=media-libs/harfbuzz-0.9.10 >=dev-libs/icu-50 needs to read xetex? ( >=media-libs/harfbuzz-0.9.10[icu] >=dev-libs/icu-50 or you get an error about missing hb-icu.h when building texlive-core if you don't have harfbuzz built with icu support.
applied, thanks!