refactor initial-sysroot handling

Signed-off-by: onur-ozkan <work@onurozkan.dev>

Author: onur-ozkan

src/bootstrap/src/core/build_steps/test.rs

@@ -1062,7 +1062,7 @@ impl Step for Tidy {
         if builder.config.channel == "dev" || builder.config.channel == "nightly" {
             builder.info("fmt check");
             if builder.initial_rustfmt().is_none() {
-                let inferred_rustfmt_dir = builder.initial_rustc.parent().unwrap();
+                let inferred_rustfmt_dir = builder.initial_sysroot.join("bin");
                 eprintln!(
                     "\
 ERROR: no `rustfmt` binary found in {PATH}

src/bootstrap/src/core/config/config.rs

@@ -360,6 +360,7 @@ pub struct Config {
     pub initial_cargo: PathBuf,
     pub initial_rustc: PathBuf,
     pub initial_cargo_clippy: Option<PathBuf>,
+    pub initial_sysroot: PathBuf,
 
     #[cfg(not(test))]
     initial_rustfmt: RefCell<RustfmtState>,
@@ -1541,8 +1542,6 @@ impl Config {
             );
         }
 
-        config.initial_cargo_clippy = cargo_clippy;
-
         config.initial_rustc = if let Some(rustc) = rustc {
             if !flags.skip_stage0_validation {
                 config.check_stage0_version(&rustc, "rustc");
@@ -1558,19 +1557,18 @@ impl Config {
                 .join(exe("rustc", config.build))
         };
 
+        config.initial_sysroot = config.initial_rustc.ancestors().nth(2).unwrap().into();
+
+        config.initial_cargo_clippy = cargo_clippy;
+
         config.initial_cargo = if let Some(cargo) = cargo {
             if !flags.skip_stage0_validation {
                 config.check_stage0_version(&cargo, "cargo");
             }
             cargo
         } else {
             config.download_beta_toolchain();
-            config
-                .out
-                .join(config.build)
-                .join("stage0")
-                .join("bin")
-                .join(exe("cargo", config.build))
+            config.initial_sysroot.join("bin").join(exe("cargo", config.build))
         };
 
         // NOTE: it's important this comes *after* we set `initial_rustc` just above.

src/bootstrap/src/core/download.rs

@@ -427,9 +427,8 @@ impl Config {
         let version = &self.stage0_metadata.compiler.version;
         let host = self.build;
 
-        let bin_root = self.out.join(host).join("stage0");
-        let clippy_stamp = bin_root.join(".clippy-stamp");
-        let cargo_clippy = bin_root.join("bin").join(exe("cargo-clippy", host));
+        let clippy_stamp = self.initial_sysroot.join(".clippy-stamp");
+        let cargo_clippy = self.initial_sysroot.join("bin").join(exe("cargo-clippy", host));
         if cargo_clippy.exists() && !program_out_of_date(&clippy_stamp, date) {
             return cargo_clippy;
         }