error: Undefined Behavior: entering unreachable code --> $DIR/cpp20_rwc_syncs.rs:LL:CC | LL | std::hint::unreachable_unchecked(); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ entering unreachable code | = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information = note: BACKTRACE: = note: inside `test_cpp20_rwc_syncs` at $DIR/cpp20_rwc_syncs.rs:LL:CC note: inside `main` at $DIR/cpp20_rwc_syncs.rs:LL:CC --> $DIR/cpp20_rwc_syncs.rs:LL:CC | LL | test_cpp20_rwc_syncs(); | ^^^^^^^^^^^^^^^^^^^^^^ note: some details are omitted, run with `MIRIFLAGS=-Zmiri-backtrace=full` for a verbose backtrace error: aborting due to previous error