Running Cython fails with 3.14.0a1 - a list attribute gets changed to `None`
Bug report
Bug description:
To be clear - this issue is just about running the Cython itself (i.e. pure Python code). It is not about compiled extension modules.
To reproduce
- Checkout Cython from git:
https://github.com/cython/cython.git git checkout daed3bce0bf0c6fb9012170cb479f64e8b9532cd(probably not important, but let's make sure we're all definitely starting from the same point).python3.14 cython.py Cython/Compiler/Parsing.py- this runs Cython on one of its own files
You get an output that ends with
File 'ExprNodes.py', line 8643, in analyse_types: TupleNode(Parsing.py:750:34,
is_sequence_constructor = 1,
result_is_used = True,
use_managed_ref = True)
Compiler crash traceback from this point on:
File "/home/dave/Documents/programming/cython2/Cython/Compiler/ExprNodes.py", line 8643, in analyse_types
if len(self.args) == 0:
~~~^^^^^^^^^^^
TypeError: object of type 'NoneType' has no len()To try to debug it some more I add a constructor to TupleNode (in Cython/Compiler/ExprNodes.py at line 8627) with a breakpoint:
def __init__(self, pos, **kw): if "args" in kw and kw['args'] is None: breakpoint() super().__init__(pos, **kw)
> <fullpath>/Cython/Compiler/ExprNodes.py(8629)__init__() -> breakpoint() (Pdb) print(kw) {'args': None} (Pdb) up > <fullpath>/Cython/Compiler/ExprNodes.py(6123)analyse_types() -> self.arg_tuple = TupleNode(self.pos, args = self.args) (Pdb) print(self.args) [<Cython.Compiler.ExprNodes.NameNode object at 0x7fb636188c80>] (Pdb)
So the the constructor call to TupleNode args is None. But in the function it's being called from it's a list containing a NameNode (which is what I think it should be). That's as far as I've got with debugging.
This has apparently been bisected to #122620 (but not by me).
CPython versions tested on:
3.14
Operating systems tested on:
Linux