diff --git a/semantic.cabal b/semantic.cabal
index 577177472..bb9af8be8 100644
--- a/semantic.cabal
+++ b/semantic.cabal
@@ -226,7 +226,7 @@ library
                      , StrictData
                      , TypeApplications
   if flag(release)
-    ghc-options:       -Wall -Wcompat -Wincomplete-record-updates -Wincomplete-uni-patterns -Wredundant-constraints -fno-warn-name-shadowing -O2 -j
+    ghc-options:       -Wall -Werror -Wcompat -Wincomplete-record-updates -Wincomplete-uni-patterns -Wredundant-constraints -fno-warn-name-shadowing -O2 -j
   else
     ghc-options:       -Wall -Wcompat -Wincomplete-record-updates -Wincomplete-uni-patterns -Wredundant-constraints -fno-warn-name-shadowing -O0 -j
   ghc-prof-options:    -fprof-auto