1 files changed, 16 insertions, 0 deletions
diff --git a/src/test/ui/impl-trait/two_tait_defining_each_other2.rs b/src/test/ui/impl-trait/two_tait_defining_each_other2.rs
new file mode 100644
index 000000000..05b096680
--- /dev/null
+++ b/src/test/ui/impl-trait/two_tait_defining_each_other2.rs
@@ -0,0 +1,16 @@
+#![feature(type_alias_impl_trait)]
+
+type A = impl Foo; //~ ERROR unconstrained opaque type
+type B = impl Foo;
+
+trait Foo {}
+
+fn muh(x: A) -> B {
+    x // B's hidden type is A (opaquely)
+    //~^ ERROR opaque type's hidden type cannot be another opaque type
+}
+
+struct Bar;
+impl Foo for Bar {}
+
+fn main() {}