mypy still segfaults on callable protocol with Self

[bodograumann]

Bug Report

mypy crashes with a Segmentation Fault when a Protocol with def __call__(self: Self) is used.

To Reproduce

Like already reported in #17314 and #16629, the following code demonstrates the issue:

from typing import Protocol, Self

class Printer(Protocol):
    def __call__(self: Self): ...

class Version:
    def __init__(self, printer: Printer): ...

Version(printer=print)

https://gist.github.com/mypy-play/cd3e93a1930402369f81735d13427eae

Expected Behavior

mypy should maybe print out some errors, but definitely not cause a Segmentation Fault.

Actual Behavior

segmentation fault (core dumped)  mypy segfault-mypy.py --show-traceback

Your Environment

• Mypy version used: 1.11.2
• Mypy command-line flags: None or --show-traceback
• Mypy configuration options from mypy.ini (and other config files): -
• Python version used: 3.12.5

[sobolevn]

I cannot reproduce locally with non-compiled build on main:

» mypy ex.py --show-traceback --show-error-codes --warn-unreachable --python-version=3.13
Success: no issues found in 1 source file

Looks like this is a mypyc issue. Or it was fixed on main 🤔