Auto merge of #102164 - compiler-errors:rpitit-foreign, r=TaKO8Ki

Serialize return-position `impl Trait` in trait hidden values in foreign libraries

Fixes #101630

2 files changed, 20 insertions, 0 deletions

diff --git a/src/test/ui/impl-trait/in-trait/auxiliary/rpitit.rs b/src/test/ui/impl-trait/in-trait/auxiliary/rpitit.rs
new file mode 100644
index 00000000000..74df300f85a
--- /dev/null
+++ b/src/test/ui/impl-trait/in-trait/auxiliary/rpitit.rs
@@ -0,0 +1,11 @@
+#![feature(return_position_impl_trait_in_trait)]
+
+pub trait Foo {
+    fn bar() -> impl Sized;
+}
+
+pub struct Foreign;
+
+impl Foo for Foreign {
+    fn bar() {}
+}
diff --git a/src/test/ui/impl-trait/in-trait/foreign.rs b/src/test/ui/impl-trait/in-trait/foreign.rs
new file mode 100644
index 00000000000..6341f5b4284
--- /dev/null
+++ b/src/test/ui/impl-trait/in-trait/foreign.rs
@@ -0,0 +1,9 @@
+// check-pass
+// aux-build: rpitit.rs
+
+extern crate rpitit;
+
+fn main() {
+    // Witness an RPITIT from another crate
+    let () = <rpitit::Foreign as rpitit::Foo>::bar();
+}