Gentoo's Bugzilla –
Attachment 592476 Details for
Bug 697492app-emulation/virtualbox-5.2.32 USE=-opus - kmk: .../work/VirtualBox-5.2.32/src/libs/Makefile.kmk:87: .../work/VirtualBox-5.2.32/src/libs/libopus-1.2.1/Makefile.kmk: No such file or directory