From 4c566617f791e3081c8ed869af352323bcc145c7 Mon Sep 17 00:00:00 2001
From: Ben Boeckel <ben.boeckel@kitware.com>
Date: Thu, 25 Aug 2016 10:41:35 -0400
Subject: [PATCH] qt: make libxcb a conditional dependency

OS X doesn't have X (usually).
---
 var/spack/repos/builtin/packages/qt/package.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/var/spack/repos/builtin/packages/qt/package.py b/var/spack/repos/builtin/packages/qt/package.py
index 81362081847..d17aacd1d37 100644
--- a/var/spack/repos/builtin/packages/qt/package.py
+++ b/var/spack/repos/builtin/packages/qt/package.py
@@ -24,6 +24,7 @@
 ##############################################################################
 from spack import *
 import os
+import sys
 
 
 class Qt(Package):
@@ -78,7 +79,7 @@ class Qt(Package):
 
     # OpenGL hardware acceleration
     depends_on("mesa", when='@4:+mesa')
-    depends_on("libxcb")
+    depends_on("libxcb", when=sys.platform != 'darwin')
 
     def url_for_version(self, version):
         # URL keeps getting more complicated with every release