error: Undefined Behavior: attempting a read access using at ALLOC[0x0], but that tag does not exist in the borrow stack for this location --> $DIR/fnentry_invalidation2.rs:LL:CC | LL | let _oof = *ptr; | ^^^^ | | | attempting a read access using 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 Stacked Borrows 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: was created by a SharedReadOnly retag at offsets [0x0..0xc] --> $DIR/fnentry_invalidation2.rs:LL:CC | LL | let ptr = t.sli.as_ptr(); | ^^^^^^^^^^^^^^ help: was later invalidated at offsets [0x0..0xc] by a Unique FnEntry retag inside this call --> $DIR/fnentry_invalidation2.rs:LL:CC | LL | let _ = t.sli.as_mut_ptr(); | ^^^^^^^^^^^^^^^^^^ = note: BACKTRACE: = note: inside `main` at $DIR/fnentry_invalidation2.rs:LL:CC note: some details are omitted, run with `MIRIFLAGS=-Zmiri-backtrace=full` for a verbose backtrace error: aborting due to previous error