src/bootstrap/build.rs

   1 use std::env;
   2 use std::path::PathBuf;
   3
   4 fn main() {
   5     println!("cargo:rerun-if-changed=build.rs");
   6     println!("cargo:rerun-if-env-changed=RUSTC");
   7     println!("cargo:rustc-env=BUILD_TRIPLE={}", env::var("HOST").unwrap());
   8
   9     // This may not be a canonicalized path.
  10     let mut rustc = PathBuf::from(env::var_os("RUSTC").unwrap());
  11
  12     if rustc.is_relative() {
  13         println!("cargo:rerun-if-env-changed=PATH");
  14         for dir in env::split_paths(&env::var_os("PATH").unwrap_or_default()) {
  15             let absolute = dir.join(&rustc);
  16             if absolute.exists() {
  17                 rustc = absolute;
  18                 break;
  19             }
  20         }
  21     }
  22     assert!(rustc.is_absolute());
  23
  24     // FIXME: if the path is not utf-8, this is going to break. Unfortunately
  25     // Cargo doesn't have a way for us to specify non-utf-8 paths easily, so
  26     // we'll need to invent some encoding scheme if this becomes a problem.
  27     println!("cargo:rustc-env=RUSTC={}", rustc.to_str().unwrap());
  28 }