mirror of https://github.com/rust-lang/rust
20 lines
475 B
Rust
20 lines
475 B
Rust
//@ build-fail
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trait ZeroSized: Sized {
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const I_AM_ZERO_SIZED: ();
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fn requires_zero_size(self);
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}
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impl<T: Sized> ZeroSized for T {
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const I_AM_ZERO_SIZED: () = [()][std::mem::size_of::<Self>()]; //~ ERROR evaluation of `<u32 as ZeroSized>::I_AM_ZERO_SIZED` failed
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fn requires_zero_size(self) {
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Self::I_AM_ZERO_SIZED;
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println!("requires_zero_size called");
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}
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}
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fn main() {
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().requires_zero_size();
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42_u32.requires_zero_size();
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}
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