1 files changed, 29 insertions, 0 deletions
diff --git a/src/test/ui/associated-types/issue-31597.rs b/src/test/ui/associated-types/issue-31597.rs
new file mode 100644
index 000000000..2872be6d6
--- /dev/null
+++ b/src/test/ui/associated-types/issue-31597.rs
@@ -0,0 +1,29 @@
+// check-pass
+#![allow(dead_code)]
+trait Make {
+    type Out;
+
+    fn make() -> Self::Out;
+}
+
+impl Make for () {
+    type Out = ();
+
+    fn make() -> Self::Out {}
+}
+
+// Also make sure we don't hit an ICE when the projection can't be known
+fn f<T: Make>() -> <T as Make>::Out { loop {} }
+
+// ...and that it works with a blanket impl
+trait Tr {
+    type Assoc;
+}
+
+impl<T: Make> Tr for T {
+    type Assoc = ();
+}
+
+fn g<T: Make>() -> <T as Tr>::Assoc { }
+
+fn main() {}