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// rust-lang/rust#60431: This is a scenario where to determine the size of
// `&Ref<Obstack>`, we need to know the concrete type of the last field in
// `Ref<Obstack>` (i.e. its "struct tail"), and determining that concrete type
// requires normalizing `Obstack::Dyn`.
//
// The old "struct tail" computation did not perform such normalization, and so
// the compiler would ICE when trying to figure out if `Ref<Obstack>` is a
// dynamically-sized type (DST).
// run-pass
use std::mem;
pub trait Arena {
type Dyn : ?Sized;
}
pub struct DynRef {
_dummy: [()],
}
pub struct Ref<A: Arena> {
_value: u8,
_dyn_arena: A::Dyn,
}
pub struct Obstack;
impl Arena for Obstack {
type Dyn = DynRef;
}
fn main() {
assert_eq!(mem::size_of::<&Ref<Obstack>>(), mem::size_of::<&[()]>());
}
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