bug#23203: 25.0.91; some loaddefs files have auto-save remnants after building (and install doesn't ignore them)

[Phillip Lord]

On Sun, April 3, 2016 8:39 pm, Eli Zaretskii wrote:
>> Date: Sun, 3 Apr 2016 20:33:37 +0100
>> From: "Phillip Lord" <phillip.lord@russet.org.uk>
>> Cc: "Phillip Lord" <phillip.lord@russet.org.uk>,
>> 23203@debbugs.gnu.org,
>> stromeko@nexgo.de
>>
>>> If needed, backups can be disabled from the command line.
>>>
>>
>> That works too (see attached diff), although it's a bit of pain because
>> of duplication in the makefile.
>
> Thanks.
>
>
>> I would ask though, when do we want backup files produced from the
>> batch-update-autoloads function?
>
> Emacs always makes backups of all the files it writes, so summarily
> exempting autoload files from this rule sounds wrong to me.  Who are we to
> dictate to the entire world out there whether they should or shouldn't
> have backups of these files?

Who are we? Well, the obvious answer is core Emacs devs with commit
privileges.

Actually, my first batch did not exempt autoload files. It only did that
when called using batch-update-autoloads: i.e. in batch, and in a function
which is commented (but not documented) to be for use during the Emacs
build process. Interactive calls to "update-directory-autoloads" and the
like would be unaffected.

I think that the comment is wrong, as I use this function outside of the
Emacs build process (and I am sure others do also), so I think we should
remove that. Alternatively, if it is right, we should move it do the
docstring.

But, I think having a "no backup files" default is still sensible for a
function used in batch; if it is always used this way in the Emacs build,
then it it telling us something. So, I would change it, and update the
docstring. We could also split the function, so that there is a version
which does not suppress backup files.