RFC 2027: "first draft" of implementation

These are a squashed series of commits.

1 files changed, 23 insertions, 0 deletions

diff --git a/src/test/ui/rfc-2027-object-safe-for-dispatch/downcast-unsafe-trait-objects.rs b/src/test/ui/rfc-2027-object-safe-for-dispatch/downcast-unsafe-trait-objects.rs
new file mode 100644
index 00000000000..fa04f4b12d5
--- /dev/null
+++ b/src/test/ui/rfc-2027-object-safe-for-dispatch/downcast-unsafe-trait-objects.rs
@@ -0,0 +1,23 @@
+// Check that we if we get ahold of an object unsafe trait
+// object with auto traits and lifetimes, we can downcast it
+//
+// check-pass
+
+#![feature(object_safe_for_dispatch)]
+
+trait Trait: Sized {}
+
+fn downcast_auto(t: &(dyn Trait + Send)) -> &dyn Trait {
+    t
+}
+
+fn downcast_lifetime<'a, 'b, 't>(t: &'a (dyn Trait + 't))
+                                 -> &'b (dyn Trait + 't)
+where
+    'a: 'b,
+    't: 'a + 'b,
+{
+    t
+}
+
+fn main() {}