diff --git a/ShellCheck.cabal b/ShellCheck.cabal
index 1226588..8afebe1 100644
--- a/ShellCheck.cabal
+++ b/ShellCheck.cabal
@@ -54,7 +54,7 @@ library
       containers           >= 0.5.6 && < 0.7,
       deepseq              >= 1.4.1 && < 1.5,
       Diff                 >= 0.4.0 && < 0.5,
-      fgl                  >= 5.7.0 && < 5.9,
+      fgl                  >= 5.7.0 && < 5.8.1.0,
       filepath             >= 1.4.0 && < 1.5,
       mtl                  >= 2.2.2 && < 2.3,
       parsec               >= 3.1.14 && < 3.2,