72 lines
1.2 KiB
Rust
72 lines
1.2 KiB
Rust
// Copyright 2019 The Fuchsia Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style license that can be
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// found in the LICENSE file.
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#![allow(warnings)]
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use std::{marker::PhantomData, option::IntoIter};
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use zerocopy::Unaligned;
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struct IsUnaligned<T: Unaligned>(T);
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// Fail compilation if `$ty: !Unaligned`.
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macro_rules! is_unaligned {
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($ty:ty) => {
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const _: () = {
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let _: IsUnaligned<$ty>;
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};
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};
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}
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// A struct is `Unaligned` if:
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// - `repr(align)` is no more than 1 and either
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// - `repr(C)` or `repr(transparent)` and
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// - all fields Unaligned
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// - `repr(packed)`
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#[derive(Unaligned)]
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#[repr(C)]
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struct Foo {
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a: u8,
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}
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is_unaligned!(Foo);
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#[derive(Unaligned)]
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#[repr(transparent)]
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struct Bar {
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a: u8,
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}
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is_unaligned!(Bar);
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#[derive(Unaligned)]
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#[repr(packed)]
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struct Baz {
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a: u16,
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}
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is_unaligned!(Baz);
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#[derive(Unaligned)]
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#[repr(C, align(1))]
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struct FooAlign {
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a: u8,
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}
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is_unaligned!(FooAlign);
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#[derive(Unaligned)]
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#[repr(C)]
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struct TypeParams<'a, T, I: Iterator> {
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a: T,
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c: I::Item,
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d: u8,
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e: PhantomData<&'a [u8]>,
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f: PhantomData<&'static str>,
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g: PhantomData<String>,
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}
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is_unaligned!(TypeParams<'static, (), IntoIter<()>>);
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