fix x clippy --stage 1

Author: jyn514

src/bootstrap/src/bin/rustc.rs

@@ -46,7 +46,8 @@ fn main() {
     // determine the version of the compiler, the real compiler needs to be
     // used. Currently, these two states are differentiated based on whether
     // --target and -vV is/isn't passed.
-    let (rustc, libdir) = if target.is_none() && version.is_none() {
+    let is_build_script = target.is_none() && version.is_none();
+    let (rustc, libdir) = if is_build_script {
         ("RUSTC_SNAPSHOT", "RUSTC_SNAPSHOT_LIBDIR")
     } else {
         ("RUSTC_REAL", "RUSTC_LIBDIR")
@@ -70,7 +71,15 @@ fn main() {
         .unwrap_or_else(|| env::var("CFG_COMPILER_HOST_TRIPLE").unwrap());
     let is_clippy = args[0].to_string_lossy().ends_with(&exe("clippy-driver", &target_name));
     let rustc_driver = if is_clippy {
-        args.remove(0)
+        if is_build_script {
+            // Don't run clippy on build scripts (for one thing, we may not have libstd built with
+            // the appropriate version yet, e.g. for stage 1 std).
+            // Also remove the `clippy-driver` param in addition to the RUSTC param.
+            args.drain(..2);
+            rustc_real
+        } else {
+            args.remove(0)
+        }
     } else {
         args.remove(0);
         rustc_real

src/bootstrap/src/core/builder.rs

@@ -1181,7 +1181,6 @@ impl<'a> Builder<'a> {
             extra_features: vec![],
         });
         let mut dylib_path = dylib_path();
-        let run_compiler = self.compiler(build_compiler.stage + 1, self.build.build);
         dylib_path.insert(0, self.sysroot(run_compiler).join("lib"));
 
         let mut cmd = Command::new(cargo_clippy.unwrap());
@@ -1634,16 +1633,6 @@ impl<'a> Builder<'a> {
             self.clear_if_dirty(&out_dir, &self.rustc(compiler));
         }
 
-        // HACK: clippy will pass `--sysroot` to `RunCompiler` if and only if SYSROOT is set and
-        // `--sysroot is not already passed. Cargo doesn't pass `--sysroot` through RUSTFLAGS for
-        // build scripts and proc-macros, which is exactly when we want to use the beta sysroot
-        // instead of the in-tree libstd. Set SYSROOT so we use beta for stage 0 build
-        if cmd == "clippy" {
-            let build_script_sysroot =
-                if stage == 0 { self.rustc_snapshot_sysroot() } else { sysroot };
-            cargo.env("SYSROOT", build_script_sysroot);
-        }
-
         // Customize the compiler we're running. Specify the compiler to cargo
         // as our shim and then pass it some various options used to configure
         // how the actual compiler itself is called.