diff --git a/var/spack/repos/builtin/packages/bison/package.py b/var/spack/repos/builtin/packages/bison/package.py
index 167171c54cfa8f..a6d2b39138ad04 100644
--- a/var/spack/repos/builtin/packages/bison/package.py
+++ b/var/spack/repos/builtin/packages/bison/package.py
@@ -31,6 +31,9 @@ class Bison(AutotoolsPackage):
 
     patch('pgi.patch', when='@3.0.4')
 
+    # Intel 14 has immature C11 support
+    conflicts('%intel@:15', when='@3.4.2:')
+
     if sys.platform == 'darwin' and macos_version() >= Version('10.13'):
         patch('secure_snprintf.patch', level=0, when='@3.0.4')