The latest version of media-libs/ilmbase in prefix-tree is media-libs/ilmbase-1.0.2, but there are ebuilds in gx86 that depend on >=media-libs/ilmbase-2.0.1, causing installation of those packages to break unless the offending package versions are manually masked.
-Wno-long-double was deprecated in configure, so trivial merge with gx86.