diff --git a/var/spack/repos/builtin/packages/krb5/package.py b/var/spack/repos/builtin/packages/krb5/package.py
index 483f6a7bfe..53993771c3 100644
--- a/var/spack/repos/builtin/packages/krb5/package.py
+++ b/var/spack/repos/builtin/packages/krb5/package.py
@@ -27,6 +27,7 @@ class Krb5(AutotoolsPackage):
     version('1.16.2', sha256='9f721e1fe593c219174740c71de514c7228a97d23eb7be7597b2ae14e487f027')
     version('1.16.1', sha256='214ffe394e3ad0c730564074ec44f1da119159d94281bbec541dc29168d21117')
 
+    depends_on('diffutils', type='build')
     depends_on('bison', type='build')
     depends_on('openssl@:1')
     depends_on('gettext')