Assertion failure when specializing functions with too many __defaults__

[brandtbucher]

When specializing some Python calls, we assert that we don't have more defaults than we have arguments. This isn't always true, though:

>>> def f():
...     pass
... 
>>> f.__defaults__ = (None,)
>>> for _ in range(2):
...     f()
... 
python: Python/specialize.c:1650: specialize_py_call: Assertion `defcount <= argcount' failed.
Aborted

Linked PRs

• GH-105840: Fix assertion failures when specializing calls with too many __defaults__ #105847
• [3.12] GH-105840: Fix assertion failures when specializing calls with too many __defaults__ (GH-105847) #105863
• [3.11] GH-105840: Fix assertion failures when specializing calls with too many __defaults__ (GH-105847) #105864