error: Undefined Behavior: Data race detected between Write on thread `` and Write on thread `` at ALLOC --> $DIR/retag_data_race_write.rs:LL:CC | LL | *p = 5; | ^^^^^^ Data race detected between Write on thread `` and Write on thread `` at ALLOC | = 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 `thread_2` at $DIR/retag_data_race_write.rs:LL:CC note: inside closure at $DIR/retag_data_race_write.rs:LL:CC --> $DIR/retag_data_race_write.rs:LL:CC | LL | let t2 = std::thread::spawn(move || thread_2(p)); | ^^^^^^^^^^^ note: some details are omitted, run with `MIRIFLAGS=-Zmiri-backtrace=full` for a verbose backtrace error: aborting due to previous error