[issue36521] Consider removing docstrings from co_consts in code objects

[Raymond Hettinger]

New submission from Raymond Hettinger <raymond.hettinger at gmail.com>:

Function objects provide __doc__ as a documented writeable attribute.  However, code objects also have the same information in co_consts[0].  When __doc__ is changed, the latter keeps a reference to the old string.  Also, the disassembly shows that co_consts[0] is never used.  Can we remove the entry in co_consts?  It looks like a compilation artifact rather than something that we need or want.


>>> def f(x):
        'y'

>>> f.__doc__
'y'
>>> f.__code__.co_consts[0]
'y'
>>> f.__doc__ = 'z'
>>> f.__code__.co_consts[0]
'y'

>>> from dis import dis
>>> dis(f)
  2           0 LOAD_CONST               1 (None)
              2 RETURN_VALUE

----------
components: Interpreter Core
messages: 339422
nosy: rhettinger
priority: normal
severity: normal
status: open
title: Consider removing docstrings from co_consts in code objects
type: resource usage
versions: Python 3.8

_______________________________________
Python tracker <report at bugs.python.org>
<https://bugs.python.org/issue36521>
_______________________________________