Bug#840927: nmu: llvm-toolchain-3.8_1:3.8.1-12
nmu llvm-toolchain-3.8_1:3.8.1-12 . mips64el . unstable . -m "rebuild to fix wrongly removed binaries (cfr: #839033)"
yes, such packages have been wrongly removed with the llvm-toolchain-snapshot decruft.
And now they are preventing 3.8 from migration.
Please binNMU them when you got why they have been removed, or whenever you prefer