stefan's blag and stuff

Blog – 2013-06-22 – McCoy again

Today I tried to use McCoy, because I want to see how the signing of update.rdf for Firefox Addons works. But … McCoy failed again with

$ ./mccoy
Couldn't load XPCOM.

So what's going on?
The problem was that libpng12 was missing again.

$ ldd xulrunner/ | grep png => not found => /usr/lib/ (0xb55a9000)

This happend because, the last time I used --onehost to install libpng. This means that it wasn't recorded in the world file of portage. The next upgrade of libpng package has removed libpng12, because nothing has depend on it. Portage (the package manager of gentoo) thought that it was an obsolete package.
Now we know better. This time we omit --oneshot argument, so libpng12 is added to the world file of portage and it's never removed again.

$ emerge =media-libs/libpng-1.2.50 -av

And a short look into the world file shows

$ cat /var/lib/portage/world

:1.2 means that libpng12 was install in a slot. Slots are used in portage to install different versions of the same package, here libpng12 and libpng15, simultaneously on the system.