Index: setup.py
--- setup.py.orig
+++ setup.py
@@ -19,9 +19,7 @@ if True:
 del sys.path[0]
 
 src_files = tuple(chain(*map(lambda x: find_c_files(x)[0], SRC_DIRS)))
-cargs = ('/O2' if iswindows else '-O3').split()
-if not iswindows:
-    cargs.extend('-std=c99 -fvisibility=hidden'.split())
+cargs = ('-std=c99 -fvisibility=hidden'.split())
 
 
 class Test(Build):