Re: [gentoo-pms] A way for trying to prevent useless rebuilds

[Pacho Ramos <pacho@gentoo.org>]

El sáb, 27-07-2013 a las 00:22 +0200, Michał Górny escribió:
> I'd go for reusing USE dependency defaults syntax, that is:
> 
>   category/foo gnome(+)
> 
> and:
> 
>   category/foo gnome(-)

Nice, I was thinking in that syntax when suggesting this ;)

> 
> And honestly, I have no idea how safe is that. We'd probably need
> version ranges to use it effectively and safely, e.g.
> 
>   ~category/foo-2..4 gnome(+)
> 

I think this only makes sense when a USE flag is changed without
bump/revbump as, otherwise, people will get a rebuild anyway, then:
=category/foo-1.x gnome(+)

should work

> No idea if and how this should interact with USE dependency defaults
> in other packages.
> 
> Ciaran will probably have more doubts.
> 

I have seen sometimes people suggesting to manually edit VDB to change
the USE flag if wanting to prevent rebuild (I remember this hack for a
change in USE flags that affected a ton of kde related packages years
ago). My idea would be that this "editing" should be done by portage (or
PM) and, then, this should be a two steps process:
1. First one should be used to change VDB
2. Second one would be to do the usual dep calculation with new VDB
information