error: Undefined Behavior: attempting a write access using <untagged> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
  --> $DIR/mut_exclusive_violation1.rs:LL:CC
   |
LL |     *LEAK = 7;
   |     ^^^^^^^^^
   |     |
   |     attempting a write access using <untagged> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
   |     this error occurs as part of an access at ALLOC[0x0..0x4]
   |
   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
   = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
help: tag was most recently created at offsets [0x0..0x4]
  --> $DIR/mut_exclusive_violation1.rs:LL:CC
   |
LL |     LEAK = x as *const _ as *mut _;
   |            ^
help: tag was later invalidated at offsets [0x0..0x4]
  --> $DIR/mut_exclusive_violation1.rs:LL:CC
   |
LL |   *our = 5;
   |   ^^^^^^^^
   = note: inside `unknown_code_2` at $DIR/mut_exclusive_violation1.rs:LL:CC
note: inside `demo_mut_advanced_unique` at $DIR/mut_exclusive_violation1.rs:LL:CC
  --> $DIR/mut_exclusive_violation1.rs:LL:CC
   |
LL |   unknown_code_2();
   |   ^^^^^^^^^^^^^^^^
note: inside `main` at $DIR/mut_exclusive_violation1.rs:LL:CC
  --> $DIR/mut_exclusive_violation1.rs:LL:CC
   |
LL |     demo_mut_advanced_unique(&mut 0);
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

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

error: aborting due to previous error