// Make sure that we cannot pass by argument a `&mut` that got already invalidated. fn foo(_: &mut i32) {} fn main() { let x = &mut 42; let xraw = x as *mut _; let xref = unsafe { &mut *xraw }; let _val = *x; // invalidate xraw foo(xref); //~ ERROR Mut reference with non-reactivatable tag Mut(Uniq }