Source: beignet Version: 1.3.2-3 Severity: important llvm-toolchain-4.0 is scheduled for removal, see #893401.
I don't know when/if LLVM 6.0 will be available for x32, but until then beignet will just be in BD-Uninstallable in x32 (which isn't a release architecture). The LLVM 3.8 build dependencies for architectures where beignet isn't built should equally be removed, just use dependencies for one LLVM version (currently 6.0) for all achitectures.