diff --git a/Modules/_ctypes/_ctypes.c b/Modules/_ctypes/_ctypes.c
index 2c2d09625a9..6d817bdaecf 100644
--- a/Modules/_ctypes/_ctypes.c
+++ b/Modules/_ctypes/_ctypes.c
@@ -3805,8 +3805,9 @@ _validate_paramflags(ctypes_state *st, PyTypeObject *type, PyObject *paramflags)
 }
 
 static int
-_get_name(PyObject *obj, const char **pname)
+_get_name(PyObject *obj, void *arg)
 {
+    const char **pname = (const char **)arg;
 #ifdef MS_WIN32
     if (PyLong_Check(obj)) {
         /* We have to use MAKEINTRESOURCEA for Windows CE.
diff --git a/Modules/_ctypes/callproc.c b/Modules/_ctypes/callproc.c
index c652634a137..80b66afb362 100644
--- a/Modules/_ctypes/callproc.c
+++ b/Modules/_ctypes/callproc.c
@@ -1353,8 +1353,9 @@ PyObject *_ctypes_callproc(ctypes_state *st,
 }
 
 static int
-_parse_voidp(PyObject *obj, void **address)
+_parse_voidp(PyObject *obj, void *arg)
 {
+    void **address = (void **)arg;
     *address = PyLong_AsVoidPtr(obj);
     if (*address == NULL)
         return 0;
@@ -1846,8 +1847,9 @@ addressof(PyObject *self, PyObject *obj)
 }
 
 static int
-converter(PyObject *obj, void **address)
+converter(PyObject *obj, void *arg)
 {
+    void **address = (void **)arg;
     *address = PyLong_AsVoidPtr(obj);
     return *address != NULL;
 }
diff --git a/Modules/_ctypes/cfield.c b/Modules/_ctypes/cfield.c
index 7086ba20106..fe0839a809f 100644
--- a/Modules/_ctypes/cfield.c
+++ b/Modules/_ctypes/cfield.c
@@ -266,7 +266,7 @@ PyCField_set(PyObject *op, PyObject *inst, PyObject *value)
 }
 
 static PyObject *
-PyCField_get(PyObject *op, PyObject *inst, PyTypeObject *type)
+PyCField_get(PyObject *op, PyObject *inst, PyObject *type)
 {
     CDataObject *src;
     CFieldObject *self = _CFieldObject_CAST(op);