rust/tests/mir-opt/const_prop/boxes.rs

20 lines
501 B
Rust

//@ test-mir-pass: GVN
//@ compile-flags: -O
// EMIT_MIR_FOR_EACH_PANIC_STRATEGY
#![feature(rustc_attrs, stmt_expr_attributes)]
// Note: this test verifies that we, in fact, do not const prop `#[rustc_box]`
// EMIT_MIR boxes.main.GVN.diff
fn main() {
// CHECK-LABEL: fn main(
// CHECK: debug x => [[x:_.*]];
// CHECK: (*{{_.*}}) = const 42_i32;
// CHECK: [[tmp:_.*]] = copy (*{{_.*}});
// CHECK: [[x]] = copy [[tmp]];
let x = *(#[rustc_box]
Box::new(42))
+ 0;
}