Bump TcLevel of failing kind equality implication

  Not bumping the TcLevel meant that we could end up
  trying to add evidence terms for the implication constraint
  created to wrap failing kind equalities (to avoid their deferral).

fixes #20043

1 files changed, 21 insertions, 0 deletions

diff --git a/testsuite/tests/typecheck/should_fail/T20043.hs b/testsuite/tests/typecheck/should_fail/T20043.hs
new file mode 100644
index 0000000000..8494537c7c
--- /dev/null
+++ b/testsuite/tests/typecheck/should_fail/T20043.hs
@@ -0,0 +1,21 @@
+{-# LANGUAGE DataKinds #-}
+{-# LANGUAGE FlexibleContexts #-}
+{-# LANGUAGE MultiParamTypeClasses #-}
+{-# LANGUAGE PolyKinds #-}
+{-# LANGUAGE ScopedTypeVariables #-}
+{-# LANGUAGE TypeApplications #-}
+{-# LANGUAGE MonoLocalBinds #-}
+{-# LANGUAGE StandaloneKindSignatures #-}
+{-# LANGUAGE UndecidableSuperClasses #-}
+
+module T20043 where
+import Data.Kind
+data T1
+data T2
+
+type All :: Type -> Type -> Constraint
+class All T1 xs => All c xs
+repo :: forall (a :: Type). All T2 a => a -> a
+repo x =
+    let y = undefined @a
+    in x