Subject: 24.3.50; C-x C-c -> Invalid function: with-current-buffer-window
From: Michael Heerdegen <[email-masked]>
To: [email-masked]
Date: Thu, 27 Mar 2014 18:42:19 +0100
List-Id: <debbugs-submit.debbugs.gnu.org>

Hello,

this kind of issue has been seen and was discussed (without a solution)
already some time ago.  Now I see an incarnation of it using the
emacs-24 branch.

I did the following (using my setup, but that probably doesn't matter):
I had a living process started from Emacs, and I hit C-x C-c.  I get his
error:

Debugger entered--Lisp error: (invalid-function with-current-buffer-window)
  with-current-buffer-window(#<buffer *Process List*> nil [lotsa byte code] nil)
  save-buffers-kill-emacs(nil)
  save-buffers-kill-terminal(nil)
  call-interactively(save-buffers-kill-terminal nil nil)
  command-execute(save-buffers-kill-terminal)

(I have removed the actual byte code).

`with-current-buffer-window' is a macro - which was defined in this
moment, of course.  When I load the source file of
save-buffers-kill-emacs, files.el, the problem is immediately fixed.
When I load the compiled files.elc again, it is there again.

What other users already had experienced was something similar: they got
an error like

    Invalid function: some-macro

where `some-macro' was a defined and well working macro.

I have an idea of what causes this: when you compile some file using a
certain macro that is not (yet) defined, and you load the resulting byte
code, and define the macro just after that, you get the same error
message.  For example, load the byte compiled code of this test file:

--8<---------------cut here---------------start------------->8---
(defun test (x)
  (unknown-macro (+ x 1)))

'(defmacro unknown-macro (&rest body) `(progn ,@body))
--8<---------------cut here---------------end--------------->8---

Now evaluate the defmacro form, and try M-: (test 1).  You get

    test: Invalid function: unknown-macro

If you eval the defun (uncompiled), the error doesn't happen.

(disassemble 'save-buffers-kill-emacs) looks here like this:

...
65	constant  with-current-buffer-window
66	constant  get-buffer-create
67	constant  "*Process List*"
68	call	  1
...

so `with-current-buffer-window' at least was not expanded while byte
compiling the source file while building.

So I think there are two problems here:

1.  While building, the compilation of file.el has to cope with an
undefined macro, which is not good (i.e., a dependency problem).

2.  Compiled code using not yet defined macros doesn't behave "as
expected".

Thanks,

Michael

In GNU Emacs 24.3.50.1 (x86_64-unknown-linux-gnu, GTK+ Version 3.10.7)
 of 2014-03-25 on drachen
Windowing system distributor `The X.Org Foundation', version 11.0.11500000
System Description:	Debian GNU/Linux testing (jessie)

Important settings:
  value of $LC_ALL: de_DE.utf8
  value of $LC_COLLATE: C
  value of $LC_TIME: C
  value of $LANG: de_DE.utf8
  locale-coding-system: utf-8-unix