add some comments.

python · gpshead · Jan 26, 2023 · Dec 11, 2022 · Dec 11, 2022 · Dec 11, 2022
commit a0b6672656a414e9f6a453f3e28b7c2e3947ab20
diff --git a/Lib/test/test_ctypes/test_parameters.py b/Lib/test/test_ctypes/test_parameters.py
@@ -273,6 +273,7 @@ def test_from_param_result_refcount(self):
         from ctypes import PyDLL, c_int, c_void_p, py_object, Structure
 
         class X(Structure):
+            """This struct size is <= sizeof(void*)."""
             _fields_ = [("a", c_void_p)]
 
             def __del__(self):
@@ -295,6 +296,7 @@ def from_param(cls, value):
         self.assertEqual(trace, [1, 2, 3, 4, 5])
 
         class Y(Structure):
+            """This struct size is > sizeof(void*)."""
             _fields_ = [("a", c_void_p), ("b", c_void_p)]
 
             def __del__(self):

diff --git a/Modules/_ctypes/_ctypes.c b/Modules/_ctypes/_ctypes.c
@@ -412,7 +412,7 @@ _ctypes_alloc_format_string_with_shape(int ndim, const Py_ssize_t *shape,
 typedef struct {
     PyObject_HEAD
     void *ptr;
-    PyObject *keep;
+    PyObject *keep;  // If set, a reference to the original CDataObject.
 } StructParamObject;