21 lines
687 B
Rust
21 lines
687 B
Rust
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// Check that deriving certain builtin traits on certain packed structs cause
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// errors. To avoid potentially misaligned references, field copies must be
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// used, which involves adding `T: Copy` bounds.
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#[derive(Copy, Clone, Default, PartialEq, Eq)]
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#[repr(packed)]
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pub struct Foo<T>(T, T, T);
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struct NonCopy;
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fn main() {
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// This one is fine because `u32` impls `Copy`.
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let x: Foo<u32> = Foo(1, 2, 3);
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_ = x.clone();
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// This one is an error because `NonCopy` doesn't impl `Copy`.
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let x: Foo<NonCopy> = Foo(NonCopy, NonCopy, NonCopy);
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_ = x.clone();
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//~^ ERROR the method `clone` exists for struct `Foo<NonCopy>`, but its trait bounds were not satisfied
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}
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