diff --git a/var/spack/repos/builtin/packages/openfst/package.py b/var/spack/repos/builtin/packages/openfst/package.py
index b75d9536f07..eed28c09620 100644
--- a/var/spack/repos/builtin/packages/openfst/package.py
+++ b/var/spack/repos/builtin/packages/openfst/package.py
@@ -31,7 +31,7 @@ class Openfst(AutotoolsPackage):
     version('1.4.0',  sha256='eb557f37560438f03912b4e43335c4c9e72aa486d4f2046127131185eb88f17a')
 
     conflicts('%intel@16:')
-    conflicts('%gcc@6:', when='@:1.6.7')
+    conflicts('%gcc@6:', when='@:1.6.1')
 
     variant('far', default=False, description="Enable FAR support")