diff --git a/Lib/distutils/util.py b/Lib/distutils/util.py
index 9a77561..8175434 100644
--- a/Lib/distutils/util.py
+++ b/Lib/distutils/util.py
@@ -143,8 +143,7 @@
                 cflags = get_config_vars().get('CFLAGS')
 
                 archs = re.findall('-arch\s+(\S+)', cflags)
-                archs.sort()
-                archs = tuple(archs)
+                archs = tuple(sorted(set(archs)))
 
                 if len(archs) == 1:
                     machine = archs[0]