message: go back to using canonicalize()
diff: @@ -10,7 +10,7 @@ use std::process::Command;
  use rustc_version::VersionMeta;
  -const XARGO_MIN_VERSION: (u32, u32, u32) = (0, 3, 20);
  +const XARGO_MIN_VERSION: (u32, u32, u32) = (0, 3, 21);
  const CARGO_MIRI_HELP: &str = r#"Interprets bin crates and tests in Miri
  @@ -258,8 +258,9 @@ fn setup(subcommand: MiriCommand) {
  // Determine where the rust sources are located. `XARGO_RUST_SRC` env var trumps everything.
  let rust_src = match std::env::var_os("XARGO_RUST_SRC") {
  Some(path) => {
  - // Make path absolute, but not via `canonicalize` (which does not work very well on Windows).
  - env::current_dir().unwrap().join(path)
  + let path = PathBuf::from(path);
  + // Make path absolute if possible.
  + path.canonicalize().unwrap_or(path)
  }
  None => {
  // Check for `rust-src` rustup component.
  