1 files changed, 14 insertions, 0 deletions
diff --git a/tests/ui/impl-trait/unsize_tuple.rs b/tests/ui/impl-trait/unsize_tuple.rs
new file mode 100644
index 00000000000..630b8fd430f
--- /dev/null
+++ b/tests/ui/impl-trait/unsize_tuple.rs
@@ -0,0 +1,14 @@
+//! Test that we do not allow unsizing `([Opaque; N],)` to `([Concrete],)`.
+
+#![feature(unsized_tuple_coercion)]
+
+fn hello() -> ([impl Sized; 2],) {
+    if false {
+        let x = hello();
+        let _: &([i32],) = &x;
+        //~^ ERROR: mismatched types
+    }
+    todo!()
+}
+
+fn main() {}