1 files changed, 26 insertions, 0 deletions
diff --git a/nixpkgs/pkgs/build-support/rust/sysroot/src.nix b/nixpkgs/pkgs/build-support/rust/sysroot/src.nix
new file mode 100644
index 000000000000..664702e82c31
--- /dev/null
+++ b/nixpkgs/pkgs/build-support/rust/sysroot/src.nix
@@ -0,0 +1,26 @@
+{ lib, stdenv, rustPlatform, buildPackages
+, originalCargoToml ? null
+}:
+
+stdenv.mkDerivation {
+  name = "cargo-src";
+  preferLocalBuild = true;
+
+  unpackPhase = "true";
+  dontConfigure = true;
+  dontBuild = true;
+
+  installPhase = ''
+    export RUSTC_SRC=${rustPlatform.rustLibSrc.override { }}
+  ''
+  + lib.optionalString (originalCargoToml != null) ''
+    export ORIG_CARGO=${originalCargoToml}
+  ''
+  + ''
+    ${buildPackages.python3.withPackages (ps: with ps; [ toml ])}/bin/python3 ${./cargo.py}
+    mkdir -p $out/src
+    echo '#![no_std]' > $out/src/lib.rs
+    cp Cargo.toml $out/Cargo.toml
+    cp ${./Cargo.lock} $out/Cargo.lock
+  '';
+}