diff --git a/setup.py b/setup.py
index af9a414..116f06f 100644
--- a/setup.py
+++ b/setup.py
@@ -1630,7 +1630,7 @@
 ##         ext = Extension('xx', ['xxmodule.c'])
 ##         self.extensions.append(ext)
 
-        if 'd' not in sys.abiflags:
+        if 'd' not in sysconfig.get_config_var('ABIFLAGS'):
             ext = Extension('xxlimited', ['xxlimited.c'],
                             define_macros=[('Py_LIMITED_API', '0x03050000')])
             self.extensions.append(ext)