bug#40975: 28.0.50; Variable gets buffer-local unexpectedly

bug#40975: 28.0.50; Variable gets buffer-local unexpectedly

[Michael Heerdegen]

Hello,

here is a reproducer:

#+begin_src emacs-lisp
(defun test ()
  (make-local-variable 'my-test-var)
  (with-current-buffer (get-buffer-create "Testbuffer")
    (setq my-test-var 27)))
#+end_src

If you eval M-: (test) e.g. in emacs -Q and inspect the binding of
`my-test-var' in "Testbuffer" and the other buffers, you'll see that the
variable has become buffer local in "Testbuffer" though it has never
been made local there.  This is the bug.

Maybe there is a problem in this case because the `setq' setting is in
the same lexical scope as the `make-local-variable' call?

TIA,

Michael.



In GNU Emacs 28.0.50 (build 57, x86_64-pc-linux-gnu, GTK+ Version 3.24.18, cairo version 1.16.0)
 of 2020-04-29 built on drachen
Repository revision: fe9be663833db1bf99f38c981378255f88ff5d06
Repository branch: master
Windowing system distributor 'The X.Org Foundation', version 11.0.12008000
System Description: Debian GNU/Linux bullseye/sid

bug#40975: 28.0.50; Variable gets buffer-local unexpectedly

[Lars Ingebrigtsen]

Michael Heerdegen <michael_heerdegen@web.de> writes:

> Hello,
>
> here is a reproducer:
>
> #+begin_src emacs-lisp
> (defun test ()
>   (make-local-variable 'my-test-var)
>   (with-current-buffer (get-buffer-create "Testbuffer")
>     (setq my-test-var 27)))
> #+end_src
>
> If you eval M-: (test) e.g. in emacs -Q and inspect the binding of
> `my-test-var' in "Testbuffer" and the other buffers, you'll see that the
> variable has become buffer local in "Testbuffer" though it has never
> been made local there.  This is the bug.

I'm seeing the opposite -- my-test-var is local to whatever buffer I
said M-: (test) in (but is unbound there), and is bound and has the
value 27 in all other buffers.

Which is what I'd expect?

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no

bug#40975: 28.0.50; Variable gets buffer-local unexpectedly

[Michael Heerdegen]

Lars Ingebrigtsen <larsi@gnus.org> writes:

> Which is what I'd expect?

Hmm - indeed, I see the same as you.

I have no explanation.  Maybe I was just wrong, or it had been an
intermediate issue, or a dynamical vs. lexical binding mode thing.  I
guess you can just close.

Thanks,

Michael.

bug#40975: 28.0.50; Variable gets buffer-local unexpectedly

[Lars Ingebrigtsen]

Michael Heerdegen <michael_heerdegen@web.de> writes:

> I have no explanation.  Maybe I was just wrong, or it had been an
> intermediate issue, or a dynamical vs. lexical binding mode thing.  I
> guess you can just close.

Perhaps you just checked in the test buffer and the original buffer and
saw that they were different, and then assumed that was because it was
local to the opposite buffer?  Or something?

Anyway, closing.

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no