rust/tests/ui/mir-dataflow/uninits-2.rs
2023-01-11 09:32:08 +00:00

25 lines
554 B
Rust

// General test of maybe_uninits state computed by MIR dataflow.
#![feature(core_intrinsics, rustc_attrs)]
use std::intrinsics::rustc_peek;
use std::mem::{drop, replace};
struct S(i32);
#[rustc_mir(rustc_peek_maybe_uninit,stop_after_dataflow)]
fn foo(x: &mut S) {
// `x` is initialized here, so maybe-uninit bit is 0.
rustc_peek(&x); //~ ERROR rustc_peek: bit not set
::std::mem::drop(x);
// `x` definitely uninitialized here, so maybe-uninit bit is 1.
rustc_peek(&x);
}
fn main() {
foo(&mut S(13));
foo(&mut S(13));
}