Merge pull request #265992 from reckenrode/unar-fix

    lib.optionals stdenv.isLinux [ gnustep.make ] ++

    lib.optionals stdenv.isDarwin [ xcbuildHook ];

  # Work around https://github.com/NixOS/nixpkgs/issues/166205.

  # xcbuild links with clang instead of clang++.

  env = lib.optionalAttrs stdenv.isDarwin {

    LD_FLAGS = "-l${stdenv.cc.libcxx.cxxabi.libName}";

  };

  xcbuildFlags = lib.optionals stdenv.isDarwin [

    "-target unar"

    "-target lsar"

    "-configuration Release"

    "MACOSX_DEPLOYMENT_TARGET=10.12"

    # Fix "ld: file not found: /nix/store/*-clang-7.1.0/lib/arc/libarclite_macosx." error

    # Disabling ARC may leak memory, however since this program is generally not used for

    # long periods of time, it shouldn't be an issue

    "CLANG_LINK_OBJC_RUNTIME=NO"

    "MACOSX_DEPLOYMENT_TARGET=${stdenv.hostPlatform.darwinMinVersion}"

  ];

  makefile = lib.optionalString (!stdenv.isDarwin) "Makefile.linux";