anchor.diff:    lldb_6 = llvmPackages_6.lldb;
     lldb_7 = llvmPackages_7.lldb;
     lldb_8 = llvmPackages_8.lldb;
  +  lldb_9 = llvmPackages_9.lldb;
   
     llvm = llvmPackages.llvm;
     llvm-manpages = llvmPackages.llvm-manpages;
   
  +  llvm_9  = llvmPackages_9.llvm;
     llvm_8  = llvmPackages_8.llvm;
     llvm_7  = llvmPackages_7.llvm;
     llvm_6  = llvmPackages_6.llvm;
  
positive.code:   llvm-polly = llvmPackages_latest.llvm-polly;
    clang-polly = llvmPackages_latest.clang.override { cc = llvmPackages_latest.clang-polly-unwrapped; };
  
    clang_8  = llvmPackages_8.clang;
    clang_7  = llvmPackages_7.clang;
    clang_6  = llvmPackages_6.clang;
  
negative.code:   lld_6 = llvmPackages_6.lld;
    lld_7 = llvmPackages_7.lld;
    lld_8 = llvmPackages_8.lld;
    lld_9 = llvmPackages_9.lld;
  
    lldb = llvmPackages.lldb;
    lldb_4 = llvmPackages_4.lldb;
  