diff options
Diffstat (limited to 'tests/ui/transmutability/unions/repr/should_handle_packed.rs')
-rw-r--r-- | tests/ui/transmutability/unions/repr/should_handle_packed.rs | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/tests/ui/transmutability/unions/repr/should_handle_packed.rs b/tests/ui/transmutability/unions/repr/should_handle_packed.rs new file mode 100644 index 000000000..24c2abd69 --- /dev/null +++ b/tests/ui/transmutability/unions/repr/should_handle_packed.rs @@ -0,0 +1,48 @@ +// check-pass +//! The presence of an `align(X)` annotation must be accounted for. + +#![crate_type = "lib"] +#![feature(transmutability)] +#![allow(dead_code, incomplete_features, non_camel_case_types)] + +mod assert { + use std::mem::{Assume, BikeshedIntrinsicFrom}; + pub struct Context; + + pub fn is_maybe_transmutable<Src, Dst>() + where + Dst: BikeshedIntrinsicFrom<Src, Context, { + Assume { + alignment: true, + lifetimes: true, + safety: true, + validity: true, + } + }> + {} +} + +fn should_pad_explicitly_packed_field() { + #[derive(Clone, Copy)] #[repr(u8)] enum V0u8 { V = 0 } + #[derive(Clone, Copy)] #[repr(u8)] enum V1u8 { V = 1 } + #[derive(Clone, Copy)] #[repr(u8)] enum V2u8 { V = 2 } + #[derive(Clone, Copy)] #[repr(u32)] enum V3u32 { V = 3 } + + #[repr(C)] + pub union Uninit { + a: (), + b: V1u8, + } + + #[repr(C, packed(2))] + pub union Packed { + a: [V3u32; 0], + b: V0u8, + } + + #[repr(C)] struct ImplicitlyPadded(Packed, V2u8); + #[repr(C)] struct ExplicitlyPadded(V0u8, Uninit, V2u8); + + assert::is_maybe_transmutable::<ImplicitlyPadded, ExplicitlyPadded>(); + assert::is_maybe_transmutable::<ExplicitlyPadded, ImplicitlyPadded>(); +} |