vlang: improve darwin situation

let

  version = "weekly.2023.19";

  ptraceSubstitution = ''

    #include <sys/types.h>

    #include <sys/ptrace.h>

  '';

  # Required for bootstrap.

  vc = fetchFromGitHub {

  vc = stdenv.mkDerivation {

    pname = "v.c";

    version = "unstable-2023-05-14";

    src = fetchFromGitHub {

      owner = "vlang";

      repo = "vc";

      rev = "f7c2b5f2a0738d0d236161c9de9f31dd0280ac86";

      sha256 = "sha256-xU3TvyNgc0o4RCsHtoC6cZTNaue2yuAiolEOvP37TKA=";

    };

    # patch the ptrace reference for darwin

    installPhase = lib.optionalString stdenv.isDarwin ''

      substituteInPlace v.c \

        --replace "#include <sys/ptrace.h>" "${ptraceSubstitution}"

    '' + ''

      mkdir -p $out

      cp v.c $out/

    '';

  };

  # Required for vdoc.

  markdown = fetchFromGitHub {

    owner = "vlang";

  ];

  env.VC = vc;

  env.VFLAGS = if stdenv.isDarwin then

    # on darwin we need to add a manual link to libgc since it doesn't have a libgc.a

    "-cg -cc ${pkgsStatic.clang}/bin/clang -no-retry-compilation -ldflags -L${pkgsStatic.boehmgc}/lib -ldflags -lgc -ldflags -L${binaryen}/lib"

  else

    # libX11.dev and xorg.xorgproto are needed because of

    # builder error: Header file <X11/Xlib.h>, needed for module `clipboard.x11` was not found. Please install a package with the X11 development headers, for example: `apt-get install libx11-dev`.

    # libXau, libxcb, libXdmcp need to be static if you use static gcc otherwise

    # /nix/store/xnk2z26fqy86xahiz3q797dzqx96sidk-glibc-2.37-8/lib/libc.so.6: undefined reference to `_rtld_glob al_ro@GLIBC_PRIVATE'

  env.VFLAGS = "-cc ${pkgsStatic.gcc}/bin/gcc -no-retry-compilation -cflags -I${xorg.libX11.dev}/include -cflags -I${xorg.xorgproto}/include -ldflags -L${binaryen}/lib -ldflags -L${pkgsStatic.xorg.libX11}/lib -ldflags -L${pkgsStatic.xorg.libxcb}/lib -ldflags -lxcb -ldflags -L${pkgsStatic.xorg.libXau}/lib -ldflags -lXau -ldflags -L${pkgsStatic.xorg.libXdmcp}/lib -ldflags -lXdmcp";

    "-cc ${pkgsStatic.gcc}/bin/gcc -no-retry-compilation -cflags -I${xorg.libX11.dev}/include -cflags -I${xorg.xorgproto}/include -ldflags -L${binaryen}/lib -ldflags -L${pkgsStatic.xorg.libX11}/lib -ldflags -L${pkgsStatic.xorg.libxcb}/lib -ldflags -lxcb -ldflags -L${pkgsStatic.xorg.libXau}/lib -ldflags -lXau -ldflags -L${pkgsStatic.xorg.libXdmcp}/lib -ldflags -lXdmcp";

  preBuild = ''

    export HOME=$(mktemp -d)

    # we don't use tcc at all since it fails on a missing libatomic

    ln -s ${pkgsStatic.tinycc}/bin/tcc ./thirdparty/tcc/tcc.exe

    cp -r ${pkgsStatic.boehmgc}/lib/* ./thirdparty/tcc/lib

  '' + lib.optionalString stdenv.isDarwin ''

    # this file isn't used by clang, but it's just to silence a warning

    # the compiler complains on an empty file, so this makes it "close" to real

    substituteInPlace vlib/builtin/builtin_d_gcboehm.c.v \

        --replace "libgc.a" "libgc.la"

  '';

  # vcreate_test.v requires git, so we must remove it when building the tools.