Gentoo's Bugzilla –
Attachment 354146 Details for
Bug 465048app-i18n/mozc-1.6.1187.102 with gcc 4.8 - protobuf/files/src/google/protobuf/stubs/strutil.h:313:25: error: typedef ‘sizeof_uint64_is_not_sizeof_long_long’ locally defined but not used [-Werror=unused-local-typedefs]