error: Undefined Behavior: Data race detected between Write on thread `main` and Write on thread `<unnamed>` at ALLOC
  --> $DIR/fence_after_load.rs:LL:CC
   |
LL |     unsafe { V = 2 }
   |              ^^^^^ Data race detected between Write on thread `main` and Write on thread `<unnamed>` 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 `main` at $DIR/fence_after_load.rs:LL:CC

note: some details are omitted, run with `MIRIFLAGS=-Zmiri-backtrace=full` for a verbose backtrace

error: aborting due to previous error