Upstream needs some time to adapt, v0.26.0rc1 (released recently):
"LLVM 7 support was originally slated for this release, but had to be delayed after some issues arose in testing. LLVM 6 is still required for llvmlite." DS -- 4096R/DF5182C8 (sten...@debian.org) http://www.danielstender.com/
