diff --git a/src/test/codegen/box-maybe-uninit.rs b/src/test/codegen/box-maybe-uninit.rs new file mode 100644 index 0000000000000..168e1a3eba0c5 --- /dev/null +++ b/src/test/codegen/box-maybe-uninit.rs @@ -0,0 +1,23 @@ +// Copyright 2017 The Rust Project Developers. See the COPYRIGHT +// file at the top-level directory of this distribution and at +// http://rust-lang.org/COPYRIGHT. +// +// Licensed under the Apache License, Version 2.0 or the MIT license +// , at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +// compile-flags: -O +#![crate_type="lib"] +#![feature(maybe_uninit)] + +use std::mem::MaybeUninit; + +// Boxing a `MaybeUninit` value should not copy junk from the stack +#[no_mangle] +pub fn box_uninitialized() -> Box> { + // CHECK-LABEL: @box_uninitialized + // CHECK-NOT: store + Box::new(MaybeUninit::uninitialized()) +}