6e8ff99958
As of RFC 18, struct layout is undefined. Opting into a C-compatible struct layout is now down with #[repr(C)]. For consistency, specifying a packed layout is now also down with #[repr(packed)]. Both can be specified. To fix errors caused by this, just add #[repr(C)] to the structs, and change #[packed] to #[repr(packed)] Closes #14309 [breaking-change]
67 lines
1.3 KiB
Rust
67 lines
1.3 KiB
Rust
// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
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// file at the top-level directory of this distribution and at
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// http://rust-lang.org/COPYRIGHT.
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//
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// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
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// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
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// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
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// option. This file may not be copied, modified, or distributed
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// except according to those terms.
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use std::mem;
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use std::gc::Gc;
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#[repr(packed)]
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struct S4 {
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a: u8,
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b: [u8, .. 3],
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}
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#[repr(packed)]
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struct S5 {
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a: u8,
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b: u32
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}
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#[repr(packed)]
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struct S13 {
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a: i64,
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b: f32,
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c: u8,
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}
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enum Foo {
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Bar = 1,
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Baz = 2
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}
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#[repr(packed)]
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struct S3_Foo {
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a: u8,
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b: u16,
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c: Foo
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}
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#[repr(packed)]
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struct S7_Option {
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a: f32,
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b: u8,
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c: u16,
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d: Option<Gc<f64>>
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}
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// Placing packed structs in statics should work
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static TEST_S4: S4 = S4 { a: 1, b: [2, 3, 4] };
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static TEST_S5: S5 = S5 { a: 3, b: 67 };
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static TEST_S3_Foo: S3_Foo = S3_Foo { a: 1, b: 2, c: Baz };
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pub fn main() {
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assert_eq!(mem::size_of::<S4>(), 4);
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assert_eq!(mem::size_of::<S5>(), 5);
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assert_eq!(mem::size_of::<S13>(), 13);
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assert_eq!(mem::size_of::<S3_Foo>(), 3 + mem::size_of::<Foo>());
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assert_eq!(mem::size_of::<S7_Option>(), 7 + mem::size_of::<Option<Gc<f64>>>());
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}
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