answer a question from a comment
diff --git a/Python/ceval.c b/Python/ceval.c
index 99dfc2d..cc1eb97 100644
--- a/Python/ceval.c
+++ b/Python/ceval.c
@@ -3659,9 +3659,9 @@
Py_DECREF(func);
}
- /* Clear the stack of the function object and the arguments,
- in case they weren't consumed already.
- XXX(twouters) when are they not consumed already?
+ /* Clear the stack of the function object. Also removes
+ the arguments in case they weren't consumed already
+ (fast_function() and err_args() leave them on the stack).
*/
while ((*pp_stack) > pfunc) {
w = EXT_POP(*pp_stack);