如何在 Nix 环境中使 macOS 框架可用于 clang?

How can I make macOS frameworks available to clang in a Nix environment?

我在 macOS 10.13.5 上,学习 Rust 编程,我使用 Nix 来控制我的开发环境。

某些操作(例如包含 jsonwebtoken 库或安装 cargo-watch 模块)会导致构建需要似乎未安装的 macOS 框架。我收到此错误消息:

  = note: ld: framework not found CoreServices
          clang-5.0: error: linker command failed with exit code 1 (use -v to see invocation)

error: aborting due to previous error

error: failed to compile `cargo-watch v6.0.0`, intermediate artifacts can be found at `/var/folders/13/84dj8yr54_1c_pn0s8n7444h0000gn/T/cargo-install.lYPZaEduUBdu`

Caused by:
  Could not compile `cargo-watch`.

这是失败的 clang 命令的缩写版本:

error: linking with `/nix/store/9j864incgjx7kqggbpisdi3nmssy4qm5-clang-wrapper-5.0.2/bin/cc` failed: exit code: 1
  |
  = note: "/nix/store/9j864incgjx7kqggbpisdi3nmssy4qm5-clang-wrapper-5.0.2/bin/cc" "-m64" "-L" ... "/nix/store/rfp87664xzhl6zv7dx5c1hixasqfxkp4-rustc-1.24.0/lib/rustlib/x86_64-apple-darwin/lib/libcompiler_builtins-ba331b20e371c580.rlib" "-framework" "CoreServices" "-framework" "CoreServices" "-l" "System" "-l" "resolv" "-l" "pthread" "-l" "c" "-l" "m"

我发现要尝试的唯一一件事是将框架添加到我的 PATH,但是这个答案是错误的,或者 PATH 环境变量无法一直通过货物到达我正在做的事情有问题的构建。

如何告诉 clang 到哪里寻找框架?它是否涉及对我的工作环境的更改,或者我是否需要考虑更改我要安装的 crate 的构建过程?

更多信息

我发现了clang -Xlinker -v命令,输出很有趣:

@(#)PROGRAM:ld  PROJECT:ld64-274.2
configured to support archs: armv6 armv7 armv7s arm64 i386 x86_64 x86_64h armv6m armv7k armv7m armv7em (tvOS)
Library search paths:
    /nix/store/ql6xbmdplca4sjpk0pz647p7djzri03c-libc++-5.0.2/lib
    /nix/store/rfp87664xzhl6zv7dx5c1hixasqfxkp4-rustc-1.24.0/lib
    /nix/store/ql6xbmdplca4sjpk0pz647p7djzri03c-libc++-5.0.2/lib
    /nix/store/rfp87664xzhl6zv7dx5c1hixasqfxkp4-rustc-1.24.0/lib
    /nix/store/8ykfqv6jx9jvfhnc4cdygdzg0piy8253-Libsystem-osx-10.11.6/lib
    /nix/store/4papfih2r9xlsl9m7hlisparij8k9zaq-clang-5.0.2-lib/lib
Framework search paths:
    /nix/store/hc6d711vwlwnn9swmkdpi9nbswbqg6h0-CF-osx-10.10.5/Library/Frameworks
    /nix/store/hc6d711vwlwnn9swmkdpi9nbswbqg6h0-CF-osx-10.10.5/Library/Frameworks
Undefined symbols for architecture x86_64:
  "_main", referenced from:
     implicit entry/start for main executable
ld: symbol(s) not found for architecture x86_64
clang-5.0: error: linker command failed with exit code 1 (use -v to see invocation)

这似乎表明我的 Nix shell 缺少某些东西,而不是操作系统甚至 clang 本身。

显然,Nix 都为标准 Apple 框架 提供了足够的沙盒环境,标准框架不可用。

我为这个解决方案发现的大部分内容来自 Use proper SDK and command-line tools on OS X 10.11 and then from examining vim-plugins nix derivation

第一步是实际安装我的项目需要的框架。他们都住在nixpkgs.darwin.apple_sdk.frameworks.

这样做可以让大部分 link 正常工作,但是 _CFURLResourceIsReachable 在我的平台上是一个未定义的符号。我用更新的 NIX_LDFLAGS 变量解决了这个问题(如 vim-plugins nix 推导中所建议的那样)。我项目的最终结果是这个 shell.nix 文件:

let
    pkgs = import <stable> {};
    frameworks = pkgs.darwin.apple_sdk.frameworks;
in pkgs.stdenv.mkDerivation {
    name = "orizentic";

    buildInputs = [ pkgs.rustc
                    pkgs.cargo
                    frameworks.Security
                    frameworks.CoreFoundation
                    frameworks.CoreServices
                  ];

    shellHook = ''
        export PS1="[$name] \[$txtgrn\]\u@\h\[$txtwht\]:\[$bldpur\]\w \[$txtcyn\]$git_branch\[$txtred\]$git_dirty \[$bldylw\]$aws_env\[$txtrst\]$ "
        export NIX_LDFLAGS="-F${frameworks.CoreFoundation}/Library/Frameworks -framework CoreFoundation $NIX_LDFLAGS";
    '';
}

这给了我 cargo-watch 包(这取决于 CoreServicesCoreFoundation)。它显然也解决了 jsonwebtokenSecurity 的依赖,尽管我还没有设法验证它。