3 files changed, 2 insertions, 4 deletions
diff --git a/src/compiler/GF/Infra/CheckM.hs b/src/compiler/GF/Infra/CheckM.hs
index 3b6833f0f..c5f9ba255 100644
--- a/src/compiler/GF/Infra/CheckM.hs
+++ b/src/compiler/GF/Infra/CheckM.hs
@@ -18,6 +18,7 @@ module GF.Infra.CheckM
 	   checkIn, checkInModule, checkMap, checkMapRecover,
            parallelCheck, accumulateError, commitCheck,
 	  ) where
+import Prelude hiding ((<>)) -- GHC 8.4.1 clash with Text.PrettyPrint
 
 import GF.Data.Operations
 --import GF.Infra.Ident
diff --git a/src/compiler/GF/Infra/Location.hs b/src/compiler/GF/Infra/Location.hs
index 0bf85b37f..8447a297c 100644
--- a/src/compiler/GF/Infra/Location.hs
+++ b/src/compiler/GF/Infra/Location.hs
@@ -1,5 +1,6 @@
 -- | Source locations
 module GF.Infra.Location where
+import Prelude hiding ((<>)) -- GHC 8.4.1 clash with Text.PrettyPrint
 import GF.Text.Pretty
 
 -- ** Source locations
diff --git a/src/compiler/GF/Infra/Option.hs b/src/compiler/GF/Infra/Option.hs
index efd59ca0b..f68c7d121 100644
--- a/src/compiler/GF/Infra/Option.hs
+++ b/src/compiler/GF/Infra/Option.hs
@@ -92,8 +92,6 @@ data OutputFormat = FmtPGFPretty
                   | FmtHaskell 
                   | FmtJava
                   | FmtProlog
-                  | FmtLambdaProlog
-                  | FmtByteCode
                   | FmtBNF
                   | FmtEBNF
                   | FmtRegular
@@ -478,8 +476,6 @@ outputFormatsExpl =
      (("haskell",      FmtHaskell),"Haskell (abstract syntax)"),
      (("java",         FmtJava),"Java (abstract syntax)"),
      (("prolog",       FmtProlog),"Prolog (whole grammar)"),
-     (("lambda_prolog",FmtLambdaProlog),"LambdaProlog (abstract syntax)"),
-     (("lp_byte_code", FmtByteCode),"Bytecode for Teyjus (abstract syntax, experimental)"),
      (("bnf",          FmtBNF),"BNF (context-free grammar)"),
      (("ebnf",         FmtEBNF),"Extended BNF"),
      (("regular",      FmtRegular),"* regular grammar"),