[Nix-dev] Re: Git expression

[Marc Weber]

On Tue, Jun 17, 2008 at 10:29:53AM -0400, Isaac Dupree wrote:
>  Marc Weber wrote:
> > Ways how this could be achieved:
> > a) rebuild 3 times removing not needed parts (expensive)
> > b) build once, copy only the files you need to a new derviation store
> >   path (then the not needed parts will be garbage collected)
> > Both can lead to trouble and more time to be spend on maintainance of
> > the packages..
> 
>  thinking about (b)... Debian splits packages after they've been built, so we 
>  know that it can be done (they'll make sure of it).  The difference perhaps 
>  is that we'd put the different parts in different prefixes.  So we really 
>  should, for example, pass a different --docdir to ./configure than --prefix, 
>  which "should" make things work (probably with some build-systems and even 
>  some configure-based, there will be things that don't quite work right, so 
>  maintenance-work can at least help upstream fix those... at least, that 
>  philosophy towards upstream is GoboLinux's...)
There are more differences:
Passing different --docdir --prefix directories does not work, because
you don't know the final destination at this point, you know them after
the packages has been compiled because the hash for the doc and binary
expressions will have it listed as dependency influencing their hash.

On the other hand I don't care about the header files and I need
documentation. So there is not that much benefit.
you also need to list each dependency twice (buildInputs = [libXY_dv
libXY_runtime])
Hmm then most --find-lib-xy-in=$what_here_include_or_libs ?
will no longer work. This could all be patched though. It just seems to
be a lot of effort. Benefits and costs doesn't pay off for me.

Marc Weber