message: Change to disable mir-opt in compile-flags
diff: // ignore-windows: Concurrency on Windows is not supported yet.
  -// compile-flags: -Zmiri-disable-isolation
  +// compile-flags: -Zmiri-disable-isolation -Zmir-opt-level=0
  use std::thread::{spawn, sleep};
  use std::ptr::null_mut;
  @@ -40,9 +40,7 @@ pub fn main() {
  sleep(Duration::from_millis(1000));
  - // Read, the add 1 fixes -Z mir-opt-level=3 from removing the read via dest-prop and breaking
  - // the test.
  - stack_var + 1 //~ ERROR Data race detected between Read on Thread(id = 1) and Write on Thread(id = 2)
  + stack_var //~ ERROR Data race detected between Read on Thread(id = 1) and Write on Thread(id = 2)
  });
  let j2 = spawn(move || {
  