Re: Time to merge the pgoyette-compat branch (take two)

[Paul Goyette <paul%whooppee.com@localhost>]

On Sat, 8 Sep 2018, Martin Husemann wrote:

> On Sat, Sep 08, 2018 at 02:19:41PM +1000, matthew green wrote:
> > Greg Troxel writes:
> > > I am just barely paying attention, but I think modules working well is
> > > important, and also having minimal code for what's needed.  So if mrg's
> > > main concerns have been addressed (aliases), I'm in favor (in a somewhat
> > > weak, not really clued in sort of way) of this.
> >
> > indeed, i don't flat out object to the object/library change.
> > it's just wrong, and we should figure out how to fix it, but
> > i don't consider it a show stopper for the branch merge.
>
> Seconded.
>
> But I am not quite sure what you think is wrong about the .a method - if
> everything else is correct, it should not make a difference now - or am I
> missing something?

As far as I can tell, it has _always_ made a difference.

The original change from .a -> .o was made by maxv, in order to avoid
having to determine where a couple of support objects were needed, and
to avoid having to determine if there were any other such objects.  By
changing from .a to .o method, maxv simply ensured that these support
objects were always included in the kernel.  Unfortunately, that meant
that _everything_ in the library was included, whether or not needed
(based on the COMPAT_xx options present).

That change caused some problems with the compat_sysv module, which
Christos worked-around.  That work-around broke auto-loading of the
compat_sysv module, which was acknowledged in his commit log.

My changes on the pgoyette-compat branch simply undo Christos's change
and revert the build to the original form.  So, I'm simply undoing a
workaround and undoing the commit that introduced the need for a
work-around.  (Someone on IRC - martin@ perhaps? - recently referred
to maxv's original commit as a hack;  I agree with that assessment.)

It is quite possible that further work needs to be done in this area,
to limit the contents of the compat library to only those objects that
are needed, regardless of the library format.  If so, the need already
exists in the current HEAD code;  it is not introduced by my changes
on the branch.




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