1 files changed, 16 insertions, 0 deletions
diff --git a/src/test/ui/type-alias-impl-trait/multiple-def-uses-in-one-fn2.rs b/src/test/ui/type-alias-impl-trait/multiple-def-uses-in-one-fn2.rs
new file mode 100644
index 000000000..14510a529
--- /dev/null
+++ b/src/test/ui/type-alias-impl-trait/multiple-def-uses-in-one-fn2.rs
@@ -0,0 +1,16 @@
+// https://github.com/rust-lang/rust/issues/73481
+// This test used to cause unsoundness, since one of the two possible
+// resolutions was chosen at random instead of erroring due to conflicts.
+
+#![feature(type_alias_impl_trait)]
+
+type X<A: ToString + Clone, B: ToString + Clone> = impl ToString;
+
+fn f<A: ToString + Clone, B: ToString + Clone>(a: A, b: B) -> (X<A, B>, X<B, A>) {
+    (a.clone(), a)
+    //~^ ERROR concrete type differs from previous defining opaque type
+}
+
+fn main() {
+    println!("{}", <X<_, _> as ToString>::to_string(&f(42_i32, String::new()).1));
+}