1 // Tests that we cannot assume that an opaque type does *not* implement some
3 #![feature(type_alias_impl_trait)]
6 impl<T> OpaqueTrait for T {}
7 type OpaqueType = impl OpaqueTrait;
8 fn mk_opaque() -> OpaqueType {
16 impl<T: std::fmt::Debug> AnotherTrait for T {}
18 // This is in error, because we cannot assume that `OpaqueType: !Debug`
19 impl AnotherTrait for D<OpaqueType> {
20 //~^ ERROR conflicting implementations of trait `AnotherTrait` for type `D<OpaqueType>`