core/pkgs/by-name/mu/musl/default.nix

{
  stdenv,
  lib,
  fetchurl,
  linuxHeaders ? null,
  useBSDCompatHeaders ? true,
}:
let
  cdefs_h = fetchurl {
    name = "sys-cdefs.h";
    url = "https://git.alpinelinux.org/aports/plain/main/libc-dev/sys-cdefs.h?id=7ca0ed62d4c0d713d9c7dd5b9a077fba78bce578";
    sha256 = "16l3dqnfq0f20rzbkhc38v74nqcsh9n3f343bpczqq8b1rz6vfrh";
  };
  queue_h = fetchurl {
    name = "sys-queue.h";
    url = "http://git.alpinelinux.org/aports/plain/main/libc-dev/sys-queue.h?id=7ca0ed62d4c0d713d9c7dd5b9a077fba78bce578";
    sha256 = "12qm82id7zys92a1qh2l1qf2wqgq6jr4qlbjmqyfffz3s3nhfd61";
  };
  tree_h = fetchurl {
    name = "sys-tree.h";
    url = "http://git.alpinelinux.org/aports/plain/main/libc-dev/sys-tree.h?id=7ca0ed62d4c0d713d9c7dd5b9a077fba78bce578";
    sha256 = "14igk6k00bnpfw660qhswagyhvr0gfqg4q55dxvaaq7ikfkrir71";
  };

  stack_chk_fail_local_c = fetchurl {
    name = "__stack_chk_fail_local.c";
    url = "https://git.alpinelinux.org/aports/plain/main/musl/__stack_chk_fail_local.c?id=9afbe3cbbf4c30ff23c733218c3c03d7e8c6461d";
    sha256 = "1nhkzzy9pklgjcq2yg89d3l18jif331srd3z3vhy5qwxl1spv6i9";
  };

  # iconv tool, implemented by musl author.
  # Original: http://git.etalabs.net/cgit/noxcuse/plain/src/iconv.c?id=02d288d89683e99fd18fe9f54d4e731a6c474a4f
  # We use copy from Alpine which fixes error messages, see:
  # https://git.alpinelinux.org/aports/commit/main/musl/iconv.c?id=a3d97e95f766c9c378194ee49361b375f093b26f
  iconv_c = fetchurl {
    name = "iconv.c";
    url = "https://git.alpinelinux.org/aports/plain/main/musl/iconv.c?id=a3d97e95f766c9c378194ee49361b375f093b26f";
    sha256 = "1mzxnc2ncq8lw9x6n7p00fvfklc9p3wfv28m68j0dfz5l8q2k6pp";
  };

  arch =
    if stdenv.hostPlatform.isx86_64 then
      "x86_64"
    else if stdenv.hostPlatform.isx86_32 then
      "i386"
    else
      null;

in
stdenv.mkDerivation rec {
  pname = "musl";
  version = "1.2.3";

  src = fetchurl {
    url = "https://musl.libc.org/releases/${pname}-${version}.tar.gz";
    sha256 = "sha256-fVsLYGJSHkYn4JnkydyCSNMqMChelZt+7Kp4DPjP1KQ=";
  };

  enableParallelBuilding = true;

  # Disable auto-adding stack protector flags,
  # so musl can selectively disable as needed
  hardeningDisable = [ "stackprotector" ];

  # Leave these, be friendlier to debuggers/perf tools
  # Don't force them on, but don't force off either
  postPatch = ''
    substituteInPlace configure \
      --replace -fno-unwind-tables "" \
      --replace -fno-asynchronous-unwind-tables ""
  '';

  patches = [
    # Minor touchup to build system making dynamic linker symlink relative
    (fetchurl {
      url = "https://raw.githubusercontent.com/openwrt/openwrt/87606e25afac6776d1bbc67ed284434ec5a832b4/toolchain/musl/patches/300-relative.patch";
      sha256 = "0hfadrycb60sm6hb6by4ycgaqc9sgrhh42k39v8xpmcvdzxrsq2n";
    })

    # fix parsing lines with optional fields in fstab etc. NOTE: Remove for the next release since it has been merged upstream
    (fetchurl {
      url = "https://git.musl-libc.org/cgit/musl/patch/?id=751bee0ee727e8d8b003c87cff77ac76f1dbecd6";
      sha256 = "sha256-qCw132TCSaZrkISmtDb8Q8ufyt8sAJdwACkvfwuoi/0=";
    })
  ];
  CFLAGS = [
    "-fstack-protector-strong"
  ] ++ lib.optional stdenv.hostPlatform.isPower "-mlong-double-64";

  configureFlags = [
    "--enable-shared"
    "--enable-static"
    "--enable-debug"
    "--enable-wrapper=all"
    "--syslibdir=${placeholder "out"}/lib"
  ];

  outputs = [
    "out"
    "bin"
    "dev"
  ];

  dontDisableStatic = true;
  dontAddStaticConfigureFlags = true;
  separateDebugInfo = true;

  NIX_DONT_SET_RPATH = true;

  preBuild = ''
    ${lib.optionalString (stdenv.targetPlatform.libc == "musl" && stdenv.targetPlatform.isx86_32)
      "# the -x c flag is required since the file extension confuses gcc
    # that detect the file as a linker script.
    $CC -x c -c ${stack_chk_fail_local_c} -o __stack_chk_fail_local.o
    $AR r libssp_nonshared.a __stack_chk_fail_local.o"
    }
  '';

  postInstall =
    ''
      # Not sure why, but link in all but scsi directory as that's what uclibc/glibc do.
      # Apparently glibc provides scsi itself?
      (cd $dev/include && ln -s $(ls -d ${linuxHeaders}/include/* | grep -v "scsi$") .)

      ${lib.optionalString (
        stdenv.targetPlatform.libc == "musl" && stdenv.targetPlatform.isx86_32
      ) "install -D libssp_nonshared.a $out/lib/libssp_nonshared.a"}

      # Create 'ldd' symlink, builtin
      ln -s $out/lib/libc.so $bin/bin/ldd

      # (impure) cc wrapper around musl for interactive usuage
      for i in musl-gcc musl-clang ld.musl-clang; do
        moveToOutput bin/$i $dev
      done
      moveToOutput lib/musl-gcc.specs $dev
      substituteInPlace $dev/bin/musl-gcc \
        --replace $out/lib/musl-gcc.specs $dev/lib/musl-gcc.specs

      # provide 'iconv' utility, using just-built headers, libc/ldso
      $CC ${iconv_c} -o $bin/bin/iconv \
        -I$dev/include \
        -L$out/lib -Wl,-rpath=$out/lib \
        -lc \
        -B $out/lib \
        -Wl,-dynamic-linker=$(ls $out/lib/ld-*)
    ''
    + lib.optionalString (arch != null) ''
      # Create 'libc.musl-$arch' symlink
      ln -rs $out/lib/libc.so $out/lib/libc.musl-${arch}.so.1
    ''
    + lib.optionalString useBSDCompatHeaders ''
      install -D ${queue_h} $dev/include/sys/queue.h
      install -D ${cdefs_h} $dev/include/sys/cdefs.h
      install -D ${tree_h} $dev/include/sys/tree.h
    '';

  passthru.linuxHeaders = linuxHeaders;

  meta = with lib; {
    description = "An efficient, small, quality libc implementation";
    homepage = "https://musl.libc.org/";
    changelog = "https://git.musl-libc.org/cgit/musl/tree/WHATSNEW?h=v${version}";
    license = licenses.mit;
    platforms = [
      "aarch64-linux"
      "armv5tel-linux"
      "armv6l-linux"
      "armv7a-linux"
      "armv7l-linux"
      "i686-linux"
      "x86_64-linux"
      "m68k-linux"
      "microblaze-linux"
      "microblazeel-linux"
      "mips-linux"
      "mips64-linux"
      "mipsel-linux"
      "mips64el-linux"
      "powerpc64-linux"
      "powerpc64le-linux"
      "riscv64-linux"
      "s390x-linux"
    ];
    maintainers = with maintainers; [
      thoughtpolice
      dtzWill
    ];
  };
}