fix(xtask): properly use cargo proxy for foreign toolchains

Signed-off-by: Martin Kröning <[email protected]>

.github/workflows/ci.yml

@@ -161,6 +161,8 @@ jobs:
         with:
           components: rust-src
       - uses: mkroening/rust-toolchain-toml@main
+      - run: rustup component add llvm-tools
+        working-directory: .
       - uses: mkroening/rust-toolchain-toml@main
         with:
           toolchain-file: 'kernel/rust-toolchain.toml'

xtask/src/ci/build.rs

@@ -1,8 +1,9 @@
+use std::env;
 use std::path::PathBuf;
+use std::process::Command;
 
 use anyhow::Result;
 use clap::Args;
-use xshell::cmd;
 
 use crate::cargo_build::CargoBuild;
 
@@ -24,23 +25,25 @@ impl Build {
 			eprintln!("::group::cargo build")
 		}
 
-		let sh = crate::sh()?;
+		let mut cargo = cargo();
 
-		let _push_env = if self.package.contains("rftrace") {
-			Some(sh.push_env(
+		if self.package.contains("rftrace") {
+			cargo.env(
 				"RUSTFLAGS",
 				"-Zinstrument-mcount -Cpasses=ee-instrument<post-inline>",
-			))
-		} else {
-			None
+			);
 		};
 
-		sh.change_dir("..");
-		cmd!(sh, "cargo build")
+		cargo
+			.current_dir("..")
+			.arg("build")
 			.args(self.cargo_build.artifact.arch.ci_cargo_args())
 			.args(self.cargo_build.cargo_build_args())
-			.args(&["--package", self.package.as_str()])
-			.run()?;
+			.args(["--package", self.package.as_str()]);
+
+		eprintln!("$ {cargo:?}");
+		let status = cargo.status()?;
+		assert!(status.success());
 
 		if super::in_ci() {
 			eprintln!("::endgroup::")
@@ -53,3 +56,31 @@ impl Build {
 		self.cargo_build.artifact.ci_image(&self.package)
 	}
 }
+
+fn cargo() -> Command {
+	let cargo = {
+		let exe = format!("cargo{}", env::consts::EXE_SUFFIX);
+		// On windows, the userspace toolchain ends up in front of the rustup proxy in $PATH.
+		// To reach the rustup proxy nonetheless, we explicitly query $CARGO_HOME.
+		let mut cargo_home = PathBuf::from(env::var_os("CARGO_HOME").unwrap());
+		cargo_home.push("bin");
+		cargo_home.push(&exe);
+		if cargo_home.exists() {
+			cargo_home
+		} else {
+			PathBuf::from(exe)
+		}
+	};
+
+	let mut cargo = Command::new(cargo);
+
+	// Remove rust-toolchain-specific environment variables from kernel cargo
+	cargo.env_remove("LD_LIBRARY_PATH");
+	env::vars()
+		.filter(|(key, _value)| key.starts_with("CARGO") || key.starts_with("RUST"))
+		.for_each(|(key, _value)| {
+			cargo.env_remove(&key);
+		});
+
+	cargo
+}