anchor.diff:    parsec = null;
     pretty = null;
     process = null;
  +  rts = null;
     stm = null;
     template-haskell = null;
     terminfo = null;
  
positive.code:   deepseq = null;
    directory = null;
    filepath = null;
    bin-package-db = null;
    ghc-boot = null;
    ghc-boot-th = null;
    ghc-compact = null;
    ghci = null;
    ghc-prim = null;
    haskeline = null;
    hpc = null;
    integer-gmp = null;
  
negative.code:   inherit (pkgs) llvmPackages;
  
    # Disable GHC 8.4.x core libraries.
    array = null;
    base = null;
    binary = null;
  