1 files changed, 18 insertions, 0 deletions
diff --git a/src/test/ui/traits/impl-object-overlap-issue-23853.rs b/src/test/ui/traits/impl-object-overlap-issue-23853.rs
new file mode 100644
index 000000000..e490967b6
--- /dev/null
+++ b/src/test/ui/traits/impl-object-overlap-issue-23853.rs
@@ -0,0 +1,18 @@
+// run-pass
+// Test that we are able to compile the case where both a blanket impl
+// and the object type itself supply the required trait obligation.
+// In this case, the blanket impl for `Foo` applies to any type,
+// including `Bar`, but the object type `Bar` also implicitly supplies
+// this context.
+
+trait Foo { fn dummy(&self) { } }
+
+trait Bar: Foo { }
+
+impl<T:?Sized> Foo for T { }
+
+fn want_foo<B:?Sized+Foo>() { }
+
+fn main() {
+    want_foo::<dyn Bar>();
+}