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#![feature(core_intrinsics, rustc_attrs)]
use std::intrinsics::rustc_peek;
#[rustc_mir(rustc_peek_liveness, stop_after_dataflow)]
fn foo() {
{
let mut x: (i32, i32) = (42, 0);
// Assignment to a projection does not cause `x` to become live
unsafe { rustc_peek(x); } //~ ERROR bit not set
x.1 = 42;
x = (0, 42);
// ...but a read from a projection does.
unsafe { rustc_peek(x); }
println!("{}", x.1);
}
{
let mut x = 42;
// Derefs are treated like a read of a local even if they are on the LHS of an assignment.
let p = &mut x;
unsafe { rustc_peek(&p); }
*p = 24;
unsafe { rustc_peek(&p); } //~ ERROR bit not set
}
}
fn main() {}
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