diff options
Diffstat (limited to 'src/test/ui/traits/pointee-tail-is-generic.rs')
-rw-r--r-- | src/test/ui/traits/pointee-tail-is-generic.rs | 29 |
1 files changed, 29 insertions, 0 deletions
diff --git a/src/test/ui/traits/pointee-tail-is-generic.rs b/src/test/ui/traits/pointee-tail-is-generic.rs new file mode 100644 index 000000000..e0da0fc38 --- /dev/null +++ b/src/test/ui/traits/pointee-tail-is-generic.rs @@ -0,0 +1,29 @@ +// check-pass +// edition:2018 + +#![feature(ptr_metadata)] +#![feature(type_alias_impl_trait)] + +type Opaque = impl std::future::Future; + +fn opaque() -> Opaque { + async {} +} + +fn a<T>() { + // type parameter T is known to be sized + is_thin::<T>(); + // tail of ADT (which is a type param) is known to be sized + is_thin::<std::cell::Cell<T>>(); + // opaque type is known to be sized + is_thin::<Opaque>(); +} + +fn a2<T: Iterator>() { + // associated type is known to be sized + is_thin::<T::Item>(); +} + +fn is_thin<T: std::ptr::Pointee<Metadata = ()>>() {} + +fn main() {} |