rust/tests/fail/stacked_borrows/illegal_read_despite_exposed2.rs
2022-07-13 18:59:33 -04:00

21 lines
914 B
Rust

//@compile-flags: -Zmiri-permissive-provenance
fn main() {
unsafe {
let root = &mut 42;
let addr = root as *mut i32 as usize;
let exposed_ptr = addr as *mut i32;
// From the exposed ptr, we get a new unique ptr.
let root2 = &mut *exposed_ptr;
// let _fool = root2 as *mut _; // this would fool us, since SRW(N+1) remains on the stack
// Stack: Unknown(<N), Unique(N)
// Stack if _fool existed: Unknown(<N), Unique(N), SRW(N+1)
// And we test that it has uniqueness by doing a conflicting read.
let _val = *exposed_ptr;
// Stack: Unknown(<N), Disabled(N)
// collapsed to Unknown(<N)
// Stack if _fool existed: Unknown(<N), Disabled(N), SRW(N+1); collapsed to Unknown(<N+2) which would not cause an ERROR
let _val = *root2; //~ ERROR: /read access .* tag does not exist in the borrow stack/
}
}