diff --git a/lib/spack/spack/compilers/xl.py b/lib/spack/spack/compilers/xl.py
index fd78abd091d..61a2e730dce 100644
--- a/lib/spack/spack/compilers/xl.py
+++ b/lib/spack/spack/compilers/xl.py
@@ -25,6 +25,7 @@
 ##############################################################################
 from spack.compiler import *
 import llnl.util.tty as tty
+from spack.version import ver
 
 class Xl(Compiler):
     # Subclasses use possible names of C compiler