Re: [gentoo-dev] [RFC] More reliable hiding preserved libraries

[Maciej Mrozowski <reavertm@gmail.com>]

On Saturday 03 of April 2010 14:16:14 Fabian Groffen wrote:
> Shouldn't we fix that buildsystem then?  Do you have an example of a
> package/buildsystem that does that?
"We" already do, the thing is that maybe we don't have to.
https://bugs.gentoo.org/show_bug.cgi?id=240323
From top of my head: python having issues with sys-libs/db as well as some 
packages with readline.
 
> > It would indeed. Now when I think about it, moving stuff to preserved
> > library dir could be just done - provided it's possible - along with
> > fixing/setting DT_RPATH's in reverse runtime dependencies. This way no
> > system-wide LIBRARY_PATH's would be necessary.
> > Is it possible? Mike?
> No, unless you somehow make sure you reserve space for this, by e.g.
> setting a bogus rpath entry at buildtime.  If you want to go that route,
> you probably want to look at the Prefix' binutils-config wrapper that
> already calls the linker with added rpath arguments.  Afterwards you can
> use chrpath to set it to the correct location.  Will get messy with the
> vdb though, but if Portage's doing it, it can probably be dealt with.
Sounds messy indeed, what about hardened/SELinux/AppArmor/whatever - do they 
allow such DT_RPATH operations? It should be probably also restricted for 
binary-only packages.

On Saturday 03 of April 2010 20:51:43 Tiziano Müller wrote:
> Don't fix the hack. Remove the preserve libs "feature", make the PMs
> check for rdeps per default before unmerging things.
This will only prevent creating orphans of uninstalled libraries, what about 
upgraded ones when SOVERSION has been bumped (the most common case)? Besides I 
can already imagine PMS-related discussion regarding "make the PMs check for 
rdeps per default before unmerging things" - thx but no thx.

> Slot libraries where needed, slot dep operators (EAPI 4) will help.
Again, you suggest to SLOT every library that happened to bump SOVERSION. It's 
unrealistic. Besides library should be slotted when it's API changes, for 
source based distributions it's not needed for ABI changes - let's not confuse 
those two. Also excessive slotting increases probability of breaking library 
discovery mechanisms in various build systems (not everyone uses pkg-config).

> And if that doesn't work out we need a separate var to give the PM a hint 
when API/ABI breakages happen (such that the PM knows when to re-install the 
rev deps).
It needs PMS amended and thus GLEP. Please submit a GLEP item for this if you 
see it fit.
Anyway, as explained in OT, it's not a problem of package manager dependencies 
system but issue with broken/not smart build systems - no dependency tree 
magic will solve this issue.

-- 
regards
MM