1 files changed, 17 insertions, 0 deletions
diff --git a/tests/ui/dyn-compatibility/default-param-self-projection.rs b/tests/ui/dyn-compatibility/default-param-self-projection.rs
new file mode 100644
index 00000000000..a440cd735da
--- /dev/null
+++ b/tests/ui/dyn-compatibility/default-param-self-projection.rs
@@ -0,0 +1,17 @@
+trait A<C = <Self as D>::E> {}
+
+trait D {
+    type E;
+}
+
+impl A<()> for () {}
+impl D for () {
+    type E = ();
+}
+
+fn f() {
+    let B: &dyn A = &();
+    //~^ ERROR the type parameter `C` must be explicitly specified
+}
+
+fn main() {}