error: unsupported on types with type parameters
  --> tests/ui-stable/union.rs:33:10
   |
33 | #[derive(IntoBytes)]
   |          ^^^^^^^^^
   |
   = note: this error originates in the derive macro `IntoBytes` (in Nightly builds, run with -Z macro-backtrace for more info)

error: must be #[repr(C)], #[repr(packed)], or #[repr(transparent)]
  --> tests/ui-stable/union.rs:47:10
   |
47 | #[derive(IntoBytes)]
   |          ^^^^^^^^^
   |
   = note: this error originates in the derive macro `IntoBytes` (in Nightly builds, run with -Z macro-backtrace for more info)

error: must be #[repr(C)], #[repr(packed)], or #[repr(transparent)]
  --> tests/ui-stable/union.rs:53:10
   |
53 | #[derive(IntoBytes)]
   |          ^^^^^^^^^
   |
   = note: this error originates in the derive macro `IntoBytes` (in Nightly builds, run with -Z macro-backtrace for more info)

error: cannot derive `Unaligned` on type with alignment greater than 1
  --> tests/ui-stable/union.rs:64:11
   |
64 | #[repr(C, align(2))]
   |           ^^^^^

error: this conflicts with another representation hint
  --> tests/ui-stable/union.rs:80:16
   |
80 | #[repr(packed, align(2))]
   |                ^^^^^

error: this conflicts with another representation hint
  --> tests/ui-stable/union.rs:86:18
   |
86 | #[repr(align(1), align(2))]
   |                  ^^^^^

error: this conflicts with another representation hint
  --> tests/ui-stable/union.rs:92:18
   |
92 | #[repr(align(2), align(4))]
   |                  ^^^^^

error: must have #[repr(C)], #[repr(transparent)], or #[repr(packed)] attribute in order to guarantee this type's alignment
  --> tests/ui-stable/union.rs:97:10
   |
97 | #[derive(Unaligned)]
   |          ^^^^^^^^^
   |
   = note: this error originates in the derive macro `Unaligned` (in Nightly builds, run with -Z macro-backtrace for more info)

error: must have #[repr(C)], #[repr(transparent)], or #[repr(packed)] attribute in order to guarantee this type's alignment
   --> tests/ui-stable/union.rs:103:10
    |
103 | #[derive(Unaligned)]
    |          ^^^^^^^^^
    |
    = note: this error originates in the derive macro `Unaligned` (in Nightly builds, run with -Z macro-backtrace for more info)

warning: unexpected `cfg` condition name: `zerocopy_derive_union_into_bytes`
  --> tests/ui-stable/union.rs:39:10
   |
39 | #[derive(IntoBytes)]
   |          ^^^^^^^^^
   |
   = help: expected names are: `clippy`, `debug_assertions`, `doc`, `docsrs`, `doctest`, `feature`, `fmt_debug`, `miri`, `overflow_checks`, `panic`, `proc_macro`, `relocation_model`, `rustfmt`, `sanitize`, `sanitizer_cfi_generalize_pointers`, `sanitizer_cfi_normalize_integers`, `target_abi`, `target_arch`, `target_endian`, `target_env`, `target_family`, `target_feature`, `target_has_atomic`, `target_has_atomic_equal_alignment`, `target_has_atomic_load_store`, `target_os`, `target_pointer_width`, `target_thread_local`, `target_vendor`, `test`, `ub_checks`, `unix`, and `windows`
   = note: using a cfg inside a derive macro will use the cfgs from the destination crate and not the ones from the defining crate
   = help: try referring to `IntoBytes` crate for guidance on how handle this unexpected cfg
   = help: the derive macro `IntoBytes` may come from an old version of the `zerocopy_derive` crate, try updating your dependency with `cargo update -p zerocopy_derive`
   = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
   = note: `#[warn(unexpected_cfgs)]` on by default
   = note: this warning originates in the derive macro `IntoBytes` (in Nightly builds, run with -Z macro-backtrace for more info)

error[E0277]: the trait bound `UnsafeCell<()>: zerocopy::Immutable` is not satisfied
  --> tests/ui-stable/union.rs:24:10
   |
24 | #[derive(Immutable)]
   |          ^^^^^^^^^ the trait `zerocopy::Immutable` is not implemented for `UnsafeCell<()>`
   |
   = note: Consider adding `#[derive(Immutable)]` to `UnsafeCell<()>`
   = help: the following other types implement trait `zerocopy::Immutable`:
             &T
             &mut T
             ()
             *const T
             *mut T
             AU16
             F32<O>
             F64<O>
           and $N others
   = note: required for `ManuallyDrop<UnsafeCell<()>>` to implement `zerocopy::Immutable`
   = help: see issue #48214
   = note: this error originates in the derive macro `Immutable` (in Nightly builds, run with -Z macro-backtrace for more info)

error[E0277]: `IntoBytes2` has inter-field padding
  --> tests/ui-stable/union.rs:39:10
   |
39 | #[derive(IntoBytes)]
   |          ^^^^^^^^^ types with padding cannot implement `IntoBytes`
   |
   = note: consider using `zerocopy::Unalign` to lower the alignment of individual fields
   = note: consider adding explicit fields where padding would be
   = note: consider using `#[repr(packed)]` to remove inter-field padding
   = help: the trait `PaddingFree<IntoBytes2, true>` is not implemented for `()`
           but trait `PaddingFree<IntoBytes2, false>` is implemented for it
   = help: see issue #48214
   = note: this error originates in the derive macro `IntoBytes` (in Nightly builds, run with -Z macro-backtrace for more info)

error[E0587]: type has conflicting packed and align representation hints
  --> tests/ui-stable/union.rs:81:1
   |
81 | union Unaligned3 {
   | ^^^^^^^^^^^^^^^^

error[E0588]: packed type cannot transitively contain a `#[repr(align)]` type
   --> tests/ui-stable/union.rs:105:1
    |
105 | union Unaligned7 {
    | ^^^^^^^^^^^^^^^^
    |
note: `AU16` has a `#[repr(align)]` attribute
   --> tests/ui-stable/../include.rs
    |
    |     pub struct AU16(pub u16);
    |     ^^^^^^^^^^^^^^^