AssertionError on python 2.7.9 in Werkzeug>=0.15.3

[DOlearczyk]

When trying to create new flask object, I get following error:

>>> from flask import Flask
>>> flask_app = Flask(__name__)
python: /mnt/builds/jenkins-builds/workspace/pulsar-8/RC/icedge-apl-4/build-intel-apollolake/tmp/work/core2-64-wrs-linux/python/2.7.9-r1/Python-2.7.9/Python/symtable.c:1319: symtable_visit_params: Assertion `arg->v.Name.ctx == Param || (arg->v.Name.ctx == Store && !toplevel)' failed.
Aborted (core dumped)

This assertion error only shows up with Werkzeug version 0.15.3 and 0.15.4. It doesn't appear with version 0.15.2.

OS: Pulsar Linux 8.0.0.14
Python: 2.7.9
Flask: 1.0.2

[davidism]

@asottile 😢

It's ridiculous that direct bytecode manipulation appears to be a more stable API than the AST above it.

[davidism]

@DOlearczyk we'll try to fix this, but you're very far behind on patch updates to Python 2.7. There is no easy way we can test on different patch versions of Python, so you're always running the risk of weird bugs in this case.

[asottile]

I think I know how to fix this, but I'd like to reproduce it first, I tried with 2.7.9 but it doesn't trigger the assertion -- are you perchance using a debug build of python?

I guess I could follow my own docs for doing that 🤔

[asottile]

(I spent a ton of time trying to compile 2.7.9 on bionic, but libssl is too new for such an old python version 😆 -- ended up resorting to docker, see #1554 for the fix)