diff --git a/haddock-api/src/Haddock/Interface/Create.hs b/haddock-api/src/Haddock/Interface/Create.hs
index 696a046a62099971372f3ff2b2a175247f180e22..d6c7bb69725bca85ace45be9c8d1401cd5f2a641 100644
--- a/haddock-api/src/Haddock/Interface/Create.hs
+++ b/haddock-api/src/Haddock/Interface/Create.hs
@@ -521,7 +521,7 @@ mkMaps dflags pkgName gre instances decls thDocs = do
           ds2mdoc :: (HsDoc GhcRn) -> ErrMsgM (MDoc Name)
           ds2mdoc = processDocStringParas dflags pkgName gre . hsDocString
 
-      let cvt = M.fromList . nonDetEltsUniqMap
+      let cvt = M.fromList . nonDetUniqMapToList
 
       declDocs' <- mapM ds2mdoc (cvt declDocs)
       argDocs'  <- mapM (mapM ds2mdoc) (cvt argDocs)