Segmentation fault for TypeVar("T", bound=Callable[..., "T"])
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crash
topic-type-variables
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- Python
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Description
Crash Report
mypy runs into a segfault when using a TypeVar like this:
T = TypeVar("T", bound=Callable[..., "T"])
Traceback
Unfortunately, nothing useful shows up:
$ mypy --show-traceback /tmp/err.py
Segmentation fault
To Reproduce
$ mypy /tmp/err.py
Segmentation fault
from typing import TypeVar
from collections.abc import Callable
T = TypeVar("T", bound=Callable[..., "T"])
Your Environment
- Mypy version used: mypy 1.8.0 (compiled: yes)
- Mypy command-line flags:
mypy /tmp/err.py - Mypy configuration options from
mypy.ini(and other config files): none - Python version used: Python 3.11.7
- Operating system and version: Calculate Linux Desktop 23 Cinnamon (Distributor ID: Gentoo)
Contributor guide
First steps
- Read the whole issue, then the project's contributing guide.
- Comment on the issue to say you are picking it up — it saves two people doing the same work.
- Fork the repository and make your change on a branch.
- Open a pull request that references the issue number.
Research direction
Start by reproducing the crash with Python 3.11.7 using the command mypy /tmp/err.py and the provided TypeVar example. Trace the failure from this minimal input through mypy's type-checking path; done means the example no longer causes a segmentation fault and its behavior is covered by an appropriate regression check.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- python
- Domain
- compilers
- Issue type
- Bug
- Difficulty
- 4/5
- Estimated time
- 3-5 days
- Activity status
- Stale
- Clarity
- Mostly clear
- Newbie friendliness
- 42/100