Bug report

Checklist

• I am confident this is a bug in CPython, not a bug in a third-party project
• I have searched theCPython issue tracker,
  and am confident this bug has not been reported before

CPython versions tested on:

CPython main branch

Operating systems tested on:

Linux

Output from running 'python -VV' on the command line:

Python 3.13.0a0 (heads/main:dd32611f4f, Aug 31 2023, 20:23:23) [GCC 10.2.1 20210110]

A clear and concise description of the bug:

The following assertion fails with PEP 709 (c3b595e):

importsysf_locs=None[f_locs:=sys._getframe().f_localsforainrange(1)]assert'a'inf_locs

This was discovered when trying to inspect listcomp iteration variable underpdb, as it makes inspection of these variables impossible:

> /home/radislav/projects/cpython/listcomp.py(1)<module>()-> [print(a) for a in range(1)](Pdb) s0> /home/radislav/projects/cpython/listcomp.py(1)<module>()-> [print(a) for a in range(1)](Pdb) print(a)*** NameError: name 'a' is not defined(Pdb) s/home/radislav/projects/cpython/listcomp.py:1: RuntimeWarning: assigning None to unbound local 'a'  [print(a) for a in range(1)]--Return--> /home/radislav/projects/cpython/listcomp.py(1)<module>()->None-> [print(a) for a in range(1)]

As I can see, it happens because iteration vars are now stored in "fast hidden locals" that aren't included intoframe->f_locals on_PyFrame_FastToLocalsWithError(frame) call, and thus are not accessible throughPyFrameObjectf_locals attribute.

cc@carljm

Linked PRs

• gh-108732: include comprehension locals in frame.f_locals #109026
• [3.12] gh-108732: include comprehension locals in frame.f_locals (GH-109026) #109097