diff --git a/FormalGrammars.cabal b/FormalGrammars.cabal
--- a/FormalGrammars.cabal
+++ b/FormalGrammars.cabal
@@ -1,5 +1,5 @@
 name:           FormalGrammars
-version:        0.3.1.1
+version:        0.3.1.2
 author:         Christian Hoener zu Siederdissen, 2013-2017
 copyright:      Christian Hoener zu Siederdissen, 2013-2017
 homepage:       https://github.com/choener/FormalGrammars
@@ -11,7 +11,7 @@
 build-type:     Simple
 stability:      experimental
 cabal-version:  >= 1.10.0
-tested-with:    GHC == 7.10.3, GHC == 8.0.1
+tested-with:    GHC == 7.10.3, GHC == 8.0.2
 synopsis:       (Context-free) grammars in formal language theory
 description:
                 <http://www.bioinf.uni-leipzig.de/Software/gADP/ generalized Algebraic Dynamic Programming>
diff --git a/FormalLanguage/CFG/Parser.hs b/FormalLanguage/CFG/Parser.hs
--- a/FormalLanguage/CFG/Parser.hs
+++ b/FormalLanguage/CFG/Parser.hs
@@ -416,7 +416,7 @@
 instance (MonadPlus m, CharParsing m) => TokenParsing (GrammarParser m) where
   someSpace = buildSomeSpaceParser (() <$ space) haskellCommentStyle
 
-deriving instance MonadState GrammarEnv (Unlined (GrammarParser Parser))
+--deriving instance MonadState GrammarEnv (Unlined (GrammarParser Parser))