toolchain("atomui", function()
    set_kind("standalone")
    set_homepage("https://llvm.org/")
    set_description(
        "A collection of modular and reusable compiler and toolchain technologies")
    set_runtimes("c++_static", "c++_shared", "stdc++_static", "stdc++_shared")

    set_toolset("cc", "clang")
    set_toolset("cxx", "clang", "clang++")
    set_toolset("mxx", "clang", "clang++")
    set_toolset("mm", "clang")
    set_toolset("cpp", "clang -E")
    set_toolset("as", "clang")
    set_toolset("ld", "clang++", "clang")
    set_toolset("sh", "clang++", "clang")
    set_toolset("ar", "llvm-ar")
    set_toolset("strip", "llvm-strip")
    set_toolset("ranlib", "llvm-ranlib")
    set_toolset("objcopy", "llvm-objcopy")
    set_toolset("mrc", "llvm-rc")
    set_toolset("dlltool", "llvm-dlltool")

    on_check("check")

    on_load(function(toolchain)
        local arch = toolchain:arch()
        local target_minver = toolchain:config("target_minver")
        if xcode_sdkver and not target_minver then
            target_minver = xcode.target_minver
        end
        -- add runtimes
        if toolchain:is_plat("windows") then
            toolchain:add("runtimes", "MT", "MTd", "MD", "MDd")
        end

        -- add march flags
        local march
        if toolchain:is_plat("windows") and not is_host("windows") then
            -- cross-compilation for windows
            if toolchain:is_arch("i386", "x86") then
                march = "-target i386-pc-windows-msvc"
            else
                march = "-target x86_64-pc-windows-msvc"
            end
            toolchain:add("ldflags", "-fuse-ld=lld")
            toolchain:add("shflags", "-fuse-ld=lld")
        elseif toolchain:is_arch("x86_64", "x64") then
            march = "-m64"
        elseif toolchain:is_arch("i386", "x86") then
            march = "-m32"
        elseif toolchain:is_plat("cross") then
            local sysroot
            local sdkdir = toolchain:sdkdir()
            local bindir = toolchain:bindir()
            local cross = toolchain:cross():gsub("(.*)%-$", "%1")
            march = "--target=" .. cross
            if bindir and os.isexec(path.join(bindir, cross .. "-gcc" ..
                                                  (is_host("windows") and ".exe" or
                                                      ""))) then
                local gcc_toolchain = path.directory(bindir)
                toolchain:add("cxflags", "--gcc-toolchain=" .. gcc_toolchain)
                toolchain:add("mxflags", "--gcc-toolchain=" .. gcc_toolchain)
                toolchain:add("asflags", "--gcc-toolchain=" .. gcc_toolchain)
                toolchain:add("ldflags", "--gcc-toolchain=" .. gcc_toolchain)
                toolchain:add("shflags", "--gcc-toolchain=" .. gcc_toolchain)
            end
            if sdkdir and os.isdir(path.join(sdkdir, cross, "include")) then
                sysroot = path.join(sdkdir, cross)
            end
            if sysroot then
                if os.isdir(path.join(sysroot, "libc")) then
                    sysroot = path.join(sysroot, "libc")
                end
                toolchain:add("cxflags", "--sysroot=" .. sysroot)
                toolchain:add("mxflags", "--sysroot=" .. sysroot)
                toolchain:add("asflags", "--sysroot=" .. sysroot)
                toolchain:add("ldflags", "--sysroot=" .. sysroot)
                toolchain:add("shflags", "--sysroot=" .. sysroot)
            end
        end

        if toolchain:is_plat("macosx") then
            local appledev = toolchain:config("appledev")
            if target_minver then
                local target = ("%s-apple-macos%s"):format(arch, target_minver)
                if appledev == "catalyst" then
                    target = ("%s-apple-ios%s-macabi"):format(arch,
                                                              target_minver)
                end
                march = "-target " .. target
            end
        end

        if march then
            toolchain:add("cxflags", march)
            toolchain:add("mxflags", march)
            toolchain:add("asflags", march)
            toolchain:add("ldflags", march)
            toolchain:add("shflags", march)
        end

        -- init flags for macOS
        if toolchain:is_plat("macosx") then
            local xcode_dir = get_config("xcode")
            local xcode_sdkver = toolchain:config("xcode_sdkver")
            local xcode_sdkdir = nil
            if xcode_dir and xcode_sdkver then
                xcode_sdkdir = xcode_dir ..
                                   "/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX" ..
                                   xcode_sdkver .. ".sdk"
                toolchain:add("cxflags", {"-isysroot", xcode_sdkdir})
                toolchain:add("mxflags", {"-isysroot", xcode_sdkdir})
                toolchain:add("ldflags", {"-isysroot", xcode_sdkdir})
                toolchain:add("shflags", {"-isysroot", xcode_sdkdir})
            else
                -- @see https://github.com/xmake-io/xmake/issues/1179
                local macsdk =
                    "/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk"
                if os.exists(macsdk) then
                    toolchain:add("cxflags", {"-isysroot", macsdk})
                    toolchain:add("mxflags", {"-isysroot", macsdk})
                    toolchain:add("ldflags", {"-isysroot", macsdk})
                    toolchain:add("shflags", {"-isysroot", macsdk})
                end
            end
            toolchain:add("mxflags", "-fobjc-arc")
        end

        -- add bin search library for loading some dependent .dll files windows
        local bindir = toolchain:bindir()
        if bindir and is_host("windows") then
            toolchain:add("runenvs", "PATH", bindir)
        end
    end)
end)