bug#74413: [PATCH] Allow to store and read repository information of VCS builds

["Björn Bidar via Bug reports for GNU Emacs, the Swiss army knife of text editors" <bug-gnu-emacs@gnu.org>]

Eli Zaretskii <eliz@gnu.org> writes:

>> From: Björn Bidar <bjorn.bidar@thaodan.de>
>> Cc: Po Lu <luangruo@yahoo.com>,  74413@debbugs.gnu.org
>> Date: Mon, 18 Nov 2024 16:21:28 +0200
>> 
>> > Doesn't that go against the tendency to have _less_ detailed/private
>> > information in the build?  We've lately removed some relatively useful
>> > infos from what we report in commands that use the build information.
>> 
>> The information added is only the branch and the repository similarly as
>> used by the Android builds. There's no private information there unless
>> the exact change reference Emacs was built on is private.
>
> The branch name could be private.

That could be but at that point you wouldn't have access to the binary
that contains the information and probably wouldn't report bugs to this
tracker either I think.

> Stefan, WDYT about this feature suggestion?
>
>> > More generally, could you present the motivation and the rationale for
>> > making this information available in production builds?
>> 
>> The information wouldn't be only available to production builds but also
>> testing/developer builds that are builtin in a CI environment to
>> e.g. provide test builds for developers to use or to instruct user to
>> use to try to reproduce a bug.
>> 
>> Even for production builds it could be useful for convenience to track
>> down the exact reference/branch a build came from from, that's
>> side effect only thou.
>
> This is already available if Emacs is built in a Git repository, and
> the information is stored in the dumped Emacs.  So what is gained by
> also recording the repository version on a disk file external to
> Emacs?

The information is only stored if the worker already had git installed
and checked out the sources with git inside the worker.
Also the function currently fails unless the system the user uses also happens to
have git installed and the sources if the are installed also contain the
VCS metadata.
Storing the VCS metadata in the sources doesn't happen usually as it
increases the size of a good chunk. In my case e.g. from 188MB to 788MB.
Why not have the same feature for other platforms too?