--- a/setup.py
+++ b/setup.py
@@ -149,7 +149,7 @@
     return options
 
 
-if sys.platform == "win32":
+if sys.platform == "win32" and 'MSC' in sys.version:
     ext_options = get_config_win32(get_options())
 else:
     ext_options = get_config_posix(get_options())
