Add missing header to setup.py
diff --git a/setup.py b/setup.py
index 0cf4e47..517818e 100644
--- a/setup.py
+++ b/setup.py
@@ -13,6 +13,7 @@
 else:
     headers = [
         'include/pybind11/attr.h',
+        'include/pybind11/buffer_info.h',
         'include/pybind11/cast.h',
         'include/pybind11/chrono.h',
         'include/pybind11/class_support.h',