1 files changed, 13 insertions, 0 deletions
diff --git a/src/test/ui/type-alias-impl-trait/coherence_generalization.rs b/src/test/ui/type-alias-impl-trait/coherence_generalization.rs
new file mode 100644
index 000000000..5c9ad9498
--- /dev/null
+++ b/src/test/ui/type-alias-impl-trait/coherence_generalization.rs
@@ -0,0 +1,13 @@
+// check-pass
+
+#![feature(type_alias_impl_trait)]
+trait Trait {}
+type Opaque<T> = impl Sized;
+fn foo<T>() -> Opaque<T> {
+    ()
+}
+
+impl<T, V> Trait for (T, V, V, u32) {}
+impl<U, V> Trait for (Opaque<U>, V, i32, V) {}
+
+fn main() {}