1 files changed, 21 insertions, 0 deletions
diff --git a/src/test/ui/coherence/coherence-inherited-subtyping.rs b/src/test/ui/coherence/coherence-inherited-subtyping.rs
new file mode 100644
index 000000000..8587eb779
--- /dev/null
+++ b/src/test/ui/coherence/coherence-inherited-subtyping.rs
@@ -0,0 +1,21 @@
+// Test that two distinct impls which match subtypes of one another
+// yield coherence errors (or not) depending on the variance.
+//
+// Note: This scenario is currently accepted, but as part of the
+// universe transition (#56105) may eventually become an error.
+
+// revisions: old re
+
+struct Foo<T> {
+    t: T,
+}
+
+impl Foo<for<'a, 'b> fn(&'a u8, &'b u8) -> &'a u8> {
+    fn method1(&self) {} //~ ERROR duplicate definitions with name `method1`
+}
+
+impl Foo<for<'a> fn(&'a u8, &'a u8) -> &'a u8> {
+    fn method1(&self) {}
+}
+
+fn main() {}