Don't set RUSTC in the bootstrap build script

src/bootstrap/build.rs

@@ -1,43 +1,7 @@
-use env::consts::{EXE_EXTENSION, EXE_SUFFIX};
 use std::env;
-use std::ffi::OsString;
-use std::path::PathBuf;
-
-/// Given an executable called `name`, return the filename for the
-/// executable for a particular target.
-pub fn exe(name: &PathBuf) -> PathBuf {
- if EXE_EXTENSION != "" && name.extension() != Some(EXE_EXTENSION.as_ref()) {
- let mut name: OsString = name.clone().into();
- name.push(EXE_SUFFIX);
- name.into()
- } else {
- name.clone()
- }
-}
 
 fn main() {
  let host = env::var("HOST").unwrap();
  println!("cargo:rerun-if-changed=build.rs");
- println!("cargo:rerun-if-env-changed=RUSTC");
  println!("cargo:rustc-env=BUILD_TRIPLE={}", host);
-
- // This may not be a canonicalized path.
- let mut rustc = PathBuf::from(env::var_os("RUSTC").unwrap());
-
- if rustc.is_relative() {
- println!("cargo:rerun-if-env-changed=PATH");
- for dir in env::split_paths(&env::var_os("PATH").unwrap_or_default()) {
- let absolute = dir.join(&exe(&rustc));
- if absolute.exists() {
- rustc = absolute;
- break;
- }
- }
- }
- assert!(rustc.is_absolute());
-
- // FIXME: if the path is not utf-8, this is going to break. Unfortunately
- // Cargo doesn't have a way for us to specify non-utf-8 paths easily, so
- // we'll need to invent some encoding scheme if this becomes a problem.
- println!("cargo:rustc-env=RUSTC={}", rustc.to_str().unwrap());
 }