1 files changed, 2 insertions, 1 deletions

diff --git a/Data/OpenPGP/Util/Base.hs b/Data/OpenPGP/Util/Base.hs
index 0c888ca..b43427c 100644
--- a/Data/OpenPGP/Util/Base.hs
+++ b/Data/OpenPGP/Util/Base.hs
@@ -30,6 +30,7 @@ import qualified Crypto.Types.PubKey.ECDSA as Vincent.ECDSA
 #endif
 import qualified Crypto.PubKey.RSA as Vincent.RSA
 import qualified Crypto.Random as Vincent
+import GHC.Stack
 
 import Data.OpenPGP.Util.Fingerprint (fingerprint)
 
@@ -85,7 +86,7 @@ find_key :: OpenPGP.Message -> String -> Maybe OpenPGP.Packet
 find_key = OpenPGP.find_key (show . fingerprint)
 
 
-keyParam :: Char -> OpenPGP.Packet -> Integer
+keyParam :: HasCallStack => Char -> OpenPGP.Packet -> Integer
 keyParam c k = fromJustMPI $ lookup c (OpenPGP.key k)
  where
     fromJustMPI :: Maybe OpenPGP.MPI -> Integer