2020-10-03 17:00:18 +01:00
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// revisions: full min
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#![cfg_attr(full, allow(incomplete_features))]
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#![cfg_attr(full, feature(const_generics))]
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#![cfg_attr(min, feature(min_const_generics))]
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2020-10-02 02:21:15 +01:00
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pub const fn is_zst<T: ?Sized>() -> usize {
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if std::mem::size_of::<T>() == 0 {
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2020-10-03 17:00:18 +01:00
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//[full]~^ ERROR the size for values of type `T` cannot be known at compilation time
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2020-10-02 02:21:15 +01:00
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1
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} else {
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0
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}
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}
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pub struct AtLeastByte<T: ?Sized> {
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value: T,
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//~^ ERROR the size for values of type `T` cannot be known at compilation time
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pad: [u8; is_zst::<T>()],
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2020-10-11 16:47:45 +01:00
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//[min]~^ ERROR generic parameters must not be used inside const evaluations
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2020-10-03 17:00:18 +01:00
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//[full]~^^ ERROR evaluation of constant value failed
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2020-10-02 02:21:15 +01:00
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}
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fn main() {}
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