1 files changed, 21 insertions, 0 deletions
diff --git a/testsuite/tests/quantified-constraints/T15316.hs b/testsuite/tests/quantified-constraints/T15316.hs
new file mode 100644
index 0000000000..07539e3183
--- /dev/null
+++ b/testsuite/tests/quantified-constraints/T15316.hs
@@ -0,0 +1,21 @@
+{-# LANGUAGE RankNTypes, QuantifiedConstraints, ConstraintKinds  #-}
+-- NB: disabling these if enabled:
+{-# LANGUAGE NoUndecidableInstances, NoUndecidableSuperClasses #-}
+
+module T15316 where
+
+import Data.Proxy
+
+{-
+class Class a where
+         method :: a
+
+subsume :: (Class a => Class b) => Proxy a -> Proxy b -> ((Class a => Class b) => r) -> r
+subsume _ _ x = x
+
+value :: Proxy a -> a
+value p = subsume p p method
+-}
+
+subsume' :: Proxy c -> ((c => c) => r) -> r
+subsume' _ x = x