error: Undefined Behavior: Data race detected between (1) Write on thread `<unnamed>` and (2) Write on thread `<unnamed>` at ALLOC. (2) just happened here
  --> $DIR/retag_data_race_write.rs:LL:CC
   |
LL |         *p = 5;
   |         ^^^^^^ Data race detected between (1) Write on thread `<unnamed>` and (2) Write on thread `<unnamed>` at ALLOC. (2) just happened here
   |
help: and (1) occurred earlier here
  --> $DIR/retag_data_race_write.rs:LL:CC
   |
LL |         let _r = &mut *p;
   |                  ^^^^^^^
   = 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 (of the first span):
   = note: inside `thread_2` at $DIR/retag_data_race_write.rs:LL:CC
note: inside closure
  --> $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