message: remove compatibility code for passing miri flags via cargo arguments
diff: @@ -521,46 +521,8 @@ fn phase_cargo_miri(mut args: env::Args) {
  &host
  };
  - // Forward all further arguments. We do some processing here because we want to
  - // detect people still using the old way of passing flags to Miri
  - // (`cargo miri -- -Zmiri-foo`).
  - while let Some(arg) = args.next() {
  - cmd.arg(&arg);
  - if arg == "--" {
  - // Check if the next argument starts with `-Zmiri`. If yes, we assume
  - // this is an old-style invocation.
  - if let Some(next_arg) = args.next() {
  - if next_arg.starts_with("-Zmiri") || next_arg == "--" {
  - eprintln!(
  - "WARNING: it seems like you are setting Miri's flags in `cargo miri` the old way,\n\
  - i.e., by passing them after the first `--`. This style is deprecated; please set\n\
  - the MIRIFLAGS environment variable instead. `cargo miri run/test` now interprets\n\
  - arguments the exact same way as `cargo run/test`."
  - );
  - // Old-style invocation. Turn these into MIRIFLAGS, if there are any.
  - if next_arg != "--" {
  - let mut miriflags = env::var("MIRIFLAGS").unwrap_or_default();
  - miriflags.push(' ');
  - miriflags.push_str(&next_arg);
  - while let Some(further_arg) = args.next() {
  - if further_arg == "--" {
  - // End of the Miri flags!
  - break;
  - }
  - miriflags.push(' ');
  - miriflags.push_str(&further_arg);
  - }
  - env::set_var("MIRIFLAGS", miriflags);
  - }
  - // Pass the remaining flags to cargo.
  + // Forward all further arguments to cargo.
  cmd.args(args);
  - break;
  - }
  - // Not a Miri argument after all, make sure we pass it to cargo.
  - cmd.arg(next_arg);
  - }
  - }
  - }
  // Set `RUSTC_WRAPPER` to ourselves. Cargo will prepend that binary to its usual invocation,
  // i.e., the first argument is `rustc` -- which is what we use in `main` to distinguish
  