bpo-33012: Fix invalid function cast warnings with gcc 8 for METH_NOARGS. (GH-6030)
METH_NOARGS functions need only a single argument but they are cast
into a PyCFunction, which takes two arguments. This triggers an
invalid function cast warning in gcc8 due to the argument mismatch.
Fix this by adding a dummy unused argument.
diff --git a/Modules/_io/stringio.c b/Modules/_io/stringio.c
index 718b1ac..f280b30 100644
--- a/Modules/_io/stringio.c
+++ b/Modules/_io/stringio.c
@@ -812,7 +812,7 @@
*/
static PyObject *
-stringio_getstate(stringio *self)
+stringio_getstate(stringio *self, PyObject *Py_UNUSED(ignored))
{
PyObject *initvalue = _io_StringIO_getvalue_impl(self);
PyObject *dict;