bug#12369: 24.2.50; cl-loop: variable not left unused

[Stefan Monnier]

>>>     ;; -*- lexical-binding: t -*-
>>>     (require 'cl-lib)
>>>     (cl-loop for (rms . emacs) in nil)
>>> Byte compile this piece of code.
>>>     Warning: Unused lexical variable `rms'
>> Yes, first bug: `emacs' is not listed as unused.
> This problem is still present in Emacs 28.

Indeed, because it *is* used internally by the code expanded from the
destructuring-bind.

>>> Attempting to fix this warning by renaming rms to _rms results in
>>> another warning.
>>>     Warning: variable `_rms' not left unused
>> Yup, second bug.
> This one is fixed, though.

Hmm... I wonder what caused this change.


        Stefan