diff --git a/setup.py b/setup.py
index 6de7aae76c0..e717411c0e0 100644
--- a/setup.py
+++ b/setup.py
@@ -141,7 +141,10 @@ def build_extensions(self):
             (ccshared,opt) = sysconfig.get_config_vars('CCSHARED','OPT')
             args['compiler_so'] = compiler + ' ' + opt + ' ' + ccshared
         if linker_so is not None:
-            args['linker_so'] = linker_so + ' -shared'
+            if platform == 'darwin1':
+                args['linker_so'] = linker_so
+            else:
+                args['linker_so'] = linker_so + ' -shared'
         self.compiler.set_executables(**args)
 
         build_ext.build_extensions(self)