Resolving dependencies...
cabal: Could not resolve dependencies:
trying: llvm-tf-3.0.3.1.1 (user goal)
next goal: llvm-ffi (dependency of llvm-tf-3.0.3.1.1)
rejecting: llvm-ffi-3.0.0 (conflict: requires pkg-config package llvm==3.0,
not found in the pkg-config database)
Dependency tree exhaustively searched.