Symbol's value as variable is void: selection-coding-system

Symbol's value as variable is void: selection-coding-system

[Miles Bader]

If I do `C-h C RET' I get that error, and doing describe-variable on
`selection-coding-system' gives:

   selection-coding-system is a variable defined in `C source code'.
   It is void as a variable.

Clicking on the `C source code' link results in an error: Search failed:
"\x1fVselection-coding-system "

I see that selection-coding-system _is_ defined, using defcustom, in
lisp/select.el, and was removed from C code on 2008-02-01, but something
apparently still thinks it's defined in C code...

Emacs is from CVS trunk, checked out about an hour ago, compiled with
"make bootstrap".

-Miles

-- 
Cat, n. A soft, indestructible automaton provided by nature to be kicked when
things go wrong in the domestic circle.

Re: Symbol's value as variable is void: selection-coding-system

[Miles Bader]

I wrote:
>    selection-coding-system is a variable defined in `C source code'.
>    It is void as a variable.
>
> Emacs is from CVS trunk, checked out about an hour ago, compiled with
> "make bootstrap".

Oh, also, it's compiled without X support (configure --without-x), on a
GNU/linux x86-64 machine (fencepost).

-Miles

-- 
"1971 pickup truck; will trade for guns"

Re: Symbol's value as variable is void: selection-coding-system

[Stefan Monnier]

> If I do `C-h C RET' I get that error, and doing describe-variable on
> `selection-coding-system' gives:

>    selection-coding-system is a variable defined in `C source code'.
>    It is void as a variable.

> Clicking on the `C source code' link results in an error: Search failed:
> "\x1fVselection-coding-system "

> I see that selection-coding-system _is_ defined, using defcustom, in
> lisp/select.el, and was removed from C code on 2008-02-01, but something
> apparently still thinks it's defined in C code...

> Emacs is from CVS trunk, checked out about an hour ago, compiled with
> "make bootstrap".

I cannot reproduce this, do you still see it?  Can someone else
reproduce it?  Are you using a non-X11 build or somesuch?


        Stefan

Re: Symbol's value as variable is void: selection-coding-system

[Miles Bader]

On Fri, May 23, 2008 at 03:50:08PM -0400, Stefan Monnier wrote:
> I cannot reproduce this, do you still see it?  Can someone else
> reproduce it?  Are you using a non-X11 build or somesuch?

As I mentioned in a followup to that message, it's built without X support
(--without-x).

Thanks,

-Miles

-- 
Politics, n. A strife of interests masquerading as a contest of
principles. The conduct of public affairs for private advantage.

Re: Symbol's value as variable is void: selection-coding-system

[Stefan Monnier]

>> I cannot reproduce this, do you still see it?  Can someone else
>> reproduce it?  Are you using a non-X11 build or somesuch?

> As I mentioned in a followup to that message, it's built without X support
> (--without-x).

I think I figured it out:

- you get a "Search failed: \x1fVselection-coding-system" because Emacs
  decided the variable is defined in C, but in the DOC file, there is no
  \x1fVselection-coding-system within one of the build-files.

- Emacs decides that the variable is defined in C because it has
  a variable-documentation property with an *integer* value (the fact
  that this property is non-nil is what allows you to specify it to
  descvribe-variable even tho it's void) and it doesn't appear in
  load-history.

- It doesn't appear in load-history because it's not been defined.

- The variable-documentation property is added by Snarf-documentation,
  which is careful to skip C files other than the ones in build-files
  but is not careful to skip Elisp files that are not in load-history.

Now, why doesn't w32-valid-locales suffer from the same problem?
Because Snarf-documentation checks whether the symbol already exists
(but not whether it's bound) before adding the variable-documentation
property.  And even though the selection-coding-system variable is not
defined, the symbol appears in mule.el (set-selection-coding-system) and
mule-diag.el (describe-current-coding-system).

Incidentally M-x describe-current-coding-system RET also signals an
error that selection-coding-system is void.


        Stefan