anchor.diff:        substituteAll ${./add-flags.sh} $out/nix-support/add-flags.sh
         substituteAll ${./add-hardening.sh} $out/nix-support/add-hardening.sh
         substituteAll ${./utils.sh} $out/nix-support/utils.sh
  +
  +      ##
  +      ## Extra custom steps
  +      ##
  +
       ''
       + extraBuildCommands;
   
  
positive.code:     '';
    };
  
    buildCommand =
      ''
        set -u
  
  
negative.code: 
        echo "${libc_lib}" > $out/nix-support/orig-libc
        echo "${libc_dev}" > $out/nix-support/orig-libc-dev
  
        ##
        ## Dynamic linker support
        ##
  
        if [[ -z ''${dynamicLinker+x} ]]; then
          echo "Don't know the name of the dynamic linker for platform '${targetPlatform.config}', so guessing instead." >&2
          local dynamicLinker="${libc_lib}/lib/ld*.so.?"
        fi
  
        # Expand globs to fill array of options
        dynamicLinker=($dynamicLinker)
  
        case ''${#dynamicLinker[@]} in
          0) echo "No dynamic linker found for platform '${targetPlatform.config}'." >&2;;
          1) echo "Using dynamic linker: '$dynamicLinker'" >&2;;
          *) echo "Multiple dynamic linkers found for platform '${targetPlatform.config}'." >&2;;
        esac
  
        if [ -n "$dynamicLinker" ]; then
          echo $dynamicLinker > $out/nix-support/dynamic-linker
  
      '' + (if targetPlatform.isDarwin then ''
          printf "export LD_DYLD_PATH=%q\n" "$dynamicLinker" >> $out/nix-support/setup-hook
      '' else ''
          if [ -e ${libc_lib}/lib/32/ld-linux.so.2 ]; then
            echo ${libc_lib}/lib/32/ld-linux.so.2 > $out/nix-support/dynamic-linker-m32
          fi
  
          local ldflagsBefore=(-dynamic-linker "$dynamicLinker")
      '') + ''
        fi
  
        # The dynamic linker is passed in `ldflagsBefore' to allow
        # explicit overrides of the dynamic linker by callers to gcc/ld
        # (the *last* value counts, so ours should come first).
        printWords "''${ldflagsBefore[@]}" > $out/nix-support/libc-ldflags-before
      '')
  
      + optionalString (!nativeTools) ''
  
        ##
        ## Initial CFLAGS
        ##
  
        # GCC shows ${cc_solib}/lib in `gcc -print-search-dirs', but not
        # ${cc_solib}/lib64 (even though it does actually search there...)..
  