anchor.diff: -{ lib, stdenv, llvm_meta, src, cmake, libxml2, libllvm, version, python3
  +{ lib, stdenv, llvm_meta, src, substituteAll, cmake, libxml2, libllvm, version, python3
   , buildLlvmTools
   , fixDarwinDylibNames
   , enableManpages ? false
  
positive.code: 
      outputs = [ "out" "lib" "dev" "python" ];
  
      # Clang expects to find LLVMgold in its own prefix
      postInstall = ''
        if [ -e ${libllvm.lib}/lib/LLVMgold.so ]; then
          ln -sv ${libllvm.lib}/lib/LLVMgold.so $lib/lib
        fi
  
        ln -sv $out/bin/clang $out/bin/cpp
  
        # Move libclang to 'lib' output
  
negative.code:       ./purity.patch
        # https://reviews.llvm.org/D51899
        ./gnu-install-dirs.patch
        (substituteAll {
          src = ../../clang-11-12-LLVMgold-path.patch;
          libllvmLibdir = "${libllvm.lib}/lib";
        })
      ];
  
      postPatch = ''
  