rust/tests/ui/const-generics/const-argument-if-length.rs
2024-02-16 20:02:50 +00:00

24 lines
641 B
Rust

//@ revisions: full min
#![cfg_attr(full, feature(generic_const_exprs))]
#![cfg_attr(full, allow(incomplete_features))]
pub const fn is_zst<T: ?Sized>() -> usize {
if std::mem::size_of::<T>() == 0 {
//~^ ERROR the size for values of type `T` cannot be known at compilation time
1
} else {
0
}
}
pub struct AtLeastByte<T: ?Sized> {
value: T,
//~^ ERROR the size for values of type `T` cannot be known at compilation time
pad: [u8; is_zst::<T>()],
//[min]~^ ERROR generic parameters may not be used in const operations
//[full]~^^ ERROR unconstrained generic constant
}
fn main() {}