bootstrap no longer carries a copy of these flags

src/lib.rs

@@ -47,7 +47,5 @@ pub use crate::eval::{eval_main, create_ecx, MiriConfig};
 /// Insert rustc arguments at the beginning of the argument list that Miri wants to be
 /// set per default, for maximal validation power.
 pub fn miri_default_args() -> &'static [&'static str] {
-    // The flags here should be kept in sync with what bootstrap adds when `test-miri` is
-    // set, which happens in `bootstrap/bin/rustc.rs` in the rustc sources.
     &["-Zalways-encode-mir", "-Zmir-emit-retag", "-Zmir-opt-level=0", "--cfg=miri"]
 }