1 files changed, 60 insertions, 0 deletions
diff --git a/infra/libkookie/nixpkgs/pkgs/test/rust-sysroot/default.nix b/infra/libkookie/nixpkgs/pkgs/test/rust-sysroot/default.nix
new file mode 100644
index 000000000000..3a786ad6f00b
--- /dev/null
+++ b/infra/libkookie/nixpkgs/pkgs/test/rust-sysroot/default.nix
@@ -0,0 +1,60 @@
+{ lib, rust, rustPlatform, fetchFromGitHub }:
+
+let
+  mkBlogOsTest = target: rustPlatform.buildRustPackage rec {
+    name = "blog_os-sysroot-test";
+
+    src = fetchFromGitHub {
+        owner = "phil-opp";
+        repo = "blog_os";
+        rev = "4e38e7ddf8dd021c3cd7e4609dfa01afb827797b";
+        sha256 = "0k9ipm9ddm1bad7bs7368wzzp6xwrhyfzfpckdax54l4ffqwljcg";
+    };
+
+    cargoSha256 = "1cbcplgz28yxshyrp2krp1jphbrcqdw6wxx3rry91p7hiqyibd30";
+
+    inherit target;
+
+    RUSTFLAGS = "-C link-arg=-nostartfiles";
+
+    # Tests don't work for `no_std`. See https://os.phil-opp.com/testing/
+    doCheck = false;
+
+    meta = with lib; {
+        description = "Test for using custom sysroots with buildRustPackage";
+        maintainers = with maintainers; [ aaronjanse ];
+        platforms = lib.platforms.x86_64;
+    };
+  };
+
+  # The book uses rust-lld for linking, but rust-lld is not currently packaged for NixOS.
+  # The justification in the book for using rust-lld suggests that gcc can still be used for testing:
+  # > Instead of using the platform's default linker (which might not support Linux targets),
+  # > we use the cross platform LLD linker that is shipped with Rust for linking our kernel.
+  # https://github.com/phil-opp/blog_os/blame/7212ffaa8383122b1eb07fe1854814f99d2e1af4/blog/content/second-edition/posts/02-minimal-rust-kernel/index.md#L157
+  targetContents = {
+    "llvm-target" = "x86_64-unknown-none";
+    "data-layout" = "e-m:e-i64:64-f80:128-n8:16:32:64-S128";
+    "arch" = "x86_64";
+    "target-endian" = "little";
+    "target-pointer-width" = "64";
+    "target-c-int-width" = "32";
+    "os" = "none";
+    "executables" = true;
+    "linker-flavor" = "gcc";
+    "panic-strategy" = "abort";
+    "disable-redzone" = true;
+    "features" = "-mmx,-sse,+soft-float";
+  };
+
+in {
+  blogOS-targetByFile = mkBlogOsTest (builtins.toFile "x86_64-blog_os.json" (builtins.toJSON targetContents));
+  blogOS-targetByNix = let
+    plat = lib.systems.elaborate { config = "x86_64-none"; } // {
+      rustc = {
+        config = "x86_64-blog_os";
+        platform = targetContents;
+      };
+    };
+    in mkBlogOsTest (rust.toRustTargetSpec plat);
+}