diff --git a/setup.py b/setup.py
index 21f9c6f53..f06be8104 100644
--- a/setup.py
+++ b/setup.py
@@ -179,7 +179,7 @@ VERSION = '0.95'
 def main(modules, is_pypy):
     language = "cpp"
     includes = ['.', path.join(sys.prefix, 'include')]
-    if sys.prefix == 'darwin':
+    if sys.platform.startswith('darwin'):
         compile_options['other'].append(['-mmacosx-version-min=10.8', '-stdlib=libc++'])
         link_opions['other'].append('-lc++')
     if use_cython: