[gentoo-user] Re: emerge with --changed-use

[»Q«]

On Thu, 28 Feb 2013 15:13:31 -0800
walt <w41ter@×××××.com> wrote:

> On 02/28/2013 11:16 AM, »Q« wrote:
> > A new useflag, tinfo, has been added for ncurses.  I would have
> > expected ncurses not to be rebuilt when I specify --changed-use, but
> > portage does want to rebuild it.  This isn't causing me any problem,
> > but I'd like to understand what's going on.  I guess I should note
> > that I'm using portage-2.1.11.50 and that
>
> > I'm one of those hardheads who has USE="-*" in make.conf.
>
> Ah, a masochist.  You're perfect for gentoo ;)
>
> >  I currently have ncurses-5.9-r2 installed with
> > USE="cxx gpm static-libs unicode -ada -debug -doc -minimal -profile
> > -trace".
> >
> > $ emerge -pvuD --changed-use @world
> >
> > These are the packages that would be merged, in order:
> >
> > Calculating dependencies... done!
> > [ebuild   R    ] sys-libs/ncurses-5.9-r2:5  USE="cxx gpm static-libs
> > unicode -ada -debug -doc -minimal -profile -tinfo% -trace" 0 kB
>
> The '%' symbol just means that the tinfo flag was introduced after
> your most recent build of ncurses.  The '-' symbol means that portage
> will rebuild ncurses without tinfo -- exactly like your existing
> build of ncurses :)  Makes perfect sense if you happen to be a
> computer.
>
> My favorite peeve is when a libreoffice useflag is added for, say,
> support for Swahili or Urdu, and now I'm forced to rebuild all of
> libreoffice just to re-install libreoffice without support for Urdu
> or Swahili.  If I were a computer I'd agree immediately with that
> reasoning.

That's exactly what --changed-use is supposed to avoid, as I
understand it.

man emerge puts it this way:

  Unlike --newuse, the --changed-use option does not trigger
  reinstallation when flags that the user has not enabled are added or
  removed.