Re: sim: replacing ChangeLog files with online git logs

[Eli Zaretskii <eliz@gnu.org>]

> Cc: vapier@gentoo.org, gdb@sourceware.org
> From: Luis Machado <luis.machado@linaro.org>
> Date: Wed, 17 Mar 2021 12:22:46 -0300
> 
> Given the idea is to drop ChangeLog files for sim/ (for reasons Mike has 
> exposed), it would make no sense to keep embedding a manually-written 
> ChangeLog entry in the git commit message. So the only two sections left 
> in the commit message would be the subject line and the description.

That doesn't have to be so, though.  How to format the Git log
messages when ChangeLog files are dropped is a separate discussion.

> The list of changes would be auto-generated by a script, but it will 
> certainly be less descriptive than a manually-written ChangeLog entry. 
> It will only list things like "modified" or "new file".
> 
> > 
> > For example, in Emacs we ask contributors to format the Git log
> > messages according to ChangeLog format, and then the generated
> > ChangeLog file looks exactly like the manual one would.
> > 
> 
> I may be mistaken, but I think the idea is to drop ChangeLog 
> dependencies even from commit messages. That will simplify the 
> contribution process given ChangeLog files/entries will be 
> auto-generated by the mentioned script.

The list of files touched by a changeset can be easily generated, but
the functions/macros/classes not so easily, and not necessarily
accurately enough, even if we will use the more elaborate script that
is used by glibc.  So some information loss will be present.

OTOH, the ChangeLog-format Git log messages don't require one to have
the ChangeLog file, they just require to use the same format when
describing the changeset.  If you use Emacs to make the changes
themselves and commit the changes into Git, you just need to use the
Emacs commands to format the Git log messages, those commands will
produce the same information as the manual ChangeLog files
automatically.

If that is not an option that this community wants to adopt, then
gitlog-to-changelog is probably not the adequate solution, and we
should try using vcs-to-changelog.py (also in Gnulib).