1 files changed, 28 insertions, 0 deletions

diff --git a/tests/ui/issues/issue-41677.rs b/tests/ui/issues/issue-41677.rs
new file mode 100644
index 000000000..afddbc799
--- /dev/null
+++ b/tests/ui/issues/issue-41677.rs
@@ -0,0 +1,28 @@
+// run-pass
+// Regression test for #41677. The local variable was winding up with
+// a type `Receiver<?T, H>` where `?T` was unconstrained, because we
+// failed to enforce the WF obligations and `?T` is a bivariant type
+// parameter position.
+
+#![allow(unused_variables, dead_code)]
+
+use std::marker::PhantomData;
+
+trait Handle {
+    type Inner;
+}
+
+struct ResizingHandle<H>(PhantomData<H>);
+impl<H> Handle for ResizingHandle<H> {
+    type Inner = H;
+}
+
+struct Receiver<T, H: Handle<Inner=T>>(PhantomData<H>);
+
+fn channel<T>(size: usize) -> Receiver<T, ResizingHandle<T>> {
+    let rx = Receiver(PhantomData);
+    rx
+}
+
+fn main() {
+}