xtask: Replace rustc module with llvm-tools crate

See https://github.com/hermitcore/rusty-loader/commit/6778606fc5ce6c406600b86f242357afff59ab8d

Cargo.lock

@@ -126,6 +126,12 @@ version = "0.2.121"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "efaa7b300f3b5fe8eb6bf21ce3895e1751d9665086af2d64b42f19701015ff4f"
 
+[[package]]
+name = "llvm-tools"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "955be5d0ca0465caf127165acb47964f911e2bc26073e865deb8be7189302faf"
+
 [[package]]
 name = "log"
 version = "0.4.17"
@@ -405,15 +411,6 @@ dependencies = [
  "winapi",
 ]
 
-[[package]]
-name = "rustc_version"
-version = "0.4.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "bfa0f585226d2e68097d4f95d113b15b83a82e819ab25717ec0590d9584ef366"
-dependencies = [
- "semver",
-]
-
 [[package]]
 name = "rusty-hermit"
 version = "0.4.0"
@@ -463,12 +460,6 @@ dependencies = [
  "syn",
 ]
 
-[[package]]
-name = "semver"
-version = "1.0.6"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a4a3381e03edd24287172047536f20cabde766e2cd3e65e6b00fb3af51c4f38d"
-
 [[package]]
 name = "shell-words"
 version = "1.1.0"
@@ -603,7 +594,7 @@ version = "0.1.0"
 dependencies = [
  "anyhow",
  "goblin",
- "rustc_version",
+ "llvm-tools",
  "xflags",
  "xshell",
 ]

xtask/Cargo.toml

@@ -6,6 +6,6 @@ edition = "2021"
 [dependencies]
 anyhow = "1.0"
 goblin = { version = "0.5", default-features = false, features = ["archive", "elf32", "elf64", "std"] }
-rustc_version = "0.4"
+llvm-tools = "0.1"
 xflags = "0.2"
 xshell = "0.2"

xtask/src/main.rs

 //! See <https://github.com/matklad/cargo-xtask/>.
 
 mod flags;
-mod rustc;
 
 use std::{
 	env::{self, VarError},
@@ -11,6 +10,7 @@ use std::{
 
 use anyhow::{anyhow, Result};
 use goblin::{archive::Archive, elf64::header};
+use llvm_tools::LlvmTools;
 use xshell::{cmd, Shell};
 
 const RUSTFLAGS: &[&str] = &[
@@ -275,8 +275,11 @@ fn binutil(name: &str) -> Result<PathBuf> {
 	let exe_suffix = env::consts::EXE_SUFFIX;
 	let exe = format!("llvm-{name}{exe_suffix}");
 
-	let mut path = rustc::rustlib()?;
-	path.push(exe);
+	let path = LlvmTools::new()
+		.map_err(|err| anyhow!("{err:?}"))?
+		.tool(&exe)
+		.ok_or_else(|| anyhow!("could not find {exe}"))?;
+
 	Ok(path)
 }
 

xtask/src/rustc.rs

-//! Taken from <https://github.com/rust-embedded/cargo-binutils/blob/980607cf8e4bb1b7db5cc7a35aafa38463818f7e/src/rustc.rs>.
-
-use std::env;
-use std::path::PathBuf;
-use std::process::Command;
-
-use anyhow::Result;
-
-pub fn sysroot() -> Result<String> {
-	let rustc = env::var_os("RUSTC").unwrap_or_else(|| "rustc".into());
-	let output = Command::new(rustc).arg("--print").arg("sysroot").output()?;
-	// Note: We must trim() to remove the `\n` from the end of stdout
-	Ok(String::from_utf8(output.stdout)?.trim().to_owned())
-}
-
-// See: https://github.com/rust-lang/rust/blob/564758c4c329e89722454dd2fbb35f1ac0b8b47c/src/bootstrap/dist.rs#L2334-L2341
-pub fn rustlib() -> Result<PathBuf> {
-	let sysroot = sysroot()?;
-	let mut pathbuf = PathBuf::from(sysroot);
-	pathbuf.push("lib");
-	pathbuf.push("rustlib");
-	pathbuf.push(rustc_version::version_meta()?.host); // TODO: Prevent calling rustc_version::version_meta() multiple times
-	pathbuf.push("bin");
-	Ok(pathbuf)
-}