Re: [gentoo-user] Re: libpng12 is missing [TEMP SOLN]

[Chris Walters <cjw2004d@comcast.net>]

On 5/15/2010 11:06 AM, Roy Wright wrote:
> Argh.  Just have to vent a little.
>
> Bring up a new install on a system whose system disk died and was replaced with an SSD.  OS installed no problems.  Recovered my RAID5 and LVM JBOD volume (a GIANT THANK YOU to the mdadm and lvm2 folks!).  Then first "weekly" update hits the libpng12 issue.  No complaints, it's what I expect being at ~amd64 and the price I willing pay for the benefits of gentoo.  Another THANK YOU to the lafilefixer folks and system is up.
>
> So on to my list a applications to be installed.  Firefox check, openoffice check, handbrake...crap.  Handbrake is one of the non-standard packages that includes their own version of support libraries.  You guessed it, libpng12 dependent.  Argh!
>
> Have fun,
> Roy
>   

I had the same problem with a 'missing' libpng12.  There are 2 slots for
libpng: slot 0 and slot 1.2.  You DON'T want anything in the 1.2 slot. 
What you DO want is the lonely ebuild in the 0 slot.  Why?  It will
create the libpng12.la file that is needed for packages to find the
library.  So this is what I did:

1.  Ran "emerge -C libpng" to remove ALL versions of libpng that were
installed.
2.  Ran "emerge =libpng-1.2.43-r2".  I believe that is the version of
the slot 0 libpng.
3.  Ran "lafilefixer --justfixit" -- just in case.
4.  Re-emerged cairo to make sure it was linked to my newly installed
libpng12
5.  Belatedly realized that I should mask every version of libpng above
the slot 0 one, and did so.
6.  Ran "equery d libpng" from the 'gentoolkit' package.
7.  Re-emerged everything on that list (even Open office - ugh).

In step 7, everything compiled and installed just fine - no errors. 
From what I can see, this looks like an upstream bug, where their source
is coded to look only for libpng12, and nothing else.  For me it would
stop with an error during the linking phase, or right at the beginning
(at least those packages had checks).

I hope this helps someone.

Chris