Re: Setlist maintenance

[Marc Balmer <marc%msys.ch@localhost>]

I totally agree with Thor, for more or less the very same reasons (building 
embedded systems) and I have nothing to add - and thus allow me to top post ;)


Am 12.12.2012 um 15:37 schrieb Thor Lancelot Simon <tls%panix.com@localhost>:

> On Tue, Dec 11, 2012 at 10:11:28PM +0000, Mindaugas Rasiukevicius wrote:
>> Alistair Crooks <agc%pkgsrc.org@localhost> wrote:
>>> 
>>>    http://www.netbsd.org/~agc/gensetlist-20101031.tar.gz
>>> 
>>> I'm not proposing it be added to NetBSD, merely hoping that its
>>> presence could make set list maintenance easier.
>>> 
>>> <...>
>> 
>> Is there a reason why this was not merged?  Also, any particular reason
>> why we could not always auto-generate sets?
> 
> I do not think it is a good idea to auto-generate set lists.  I think
> there is real value to forcing the developer to actually think about
> what files he or she is causing to appear in the built system.
> 
> Unlike many other package-building systems, NetBSD's setlists really
> constrain the built system so that it contains only what is in the
> lists.  That is a good thing.  When I was building NetBSD based embedded
> systems for a living, this frequently caught cases where developers
> (ours, not NetBSD's -- but myself included) screwed up their Makefiles
> and put all kinds of random crap into the system by accident.
> 
> We were migrating away from a legacy build system that ran the native
> builds of another BSD flavor and all sorts of add-on packages, let
> them install whatever they wanted to, then tried to _delete_ anything
> anyone noticed was extra.  I can't tell you what a disaster that was.
> 
> NetBSD's setlists are also very useful for building alternate, smaller
> versions of the system -- you can build a set that is actually a small
> subset of "base" or "etc".  I think this isn't widely known, but it is
> a really neat trick (Matt Thomas pointed it out to me).  I worry that
> automatically generated setlists would bring with them unexpected
> dependencies between components which would make this harder to do, since
> we would go from actually thinking about everything any component causes
> to be in the built system to just naively accepting whatever the first
> attempt at the Makefiles happens to put there -- missing opportunities
> to pare things down or adjust them so they work better without creating
> later incompatibilities.
> 
> So, I like Alistair's tool but I strongly urge that it not be used by
> default to generate the setlists for the sets shipped as NetBSD.
> 
> Thor