Upgrading libpng: shall we move to 1.4.x or 1.5.x?

[Nils Philippsen]

On Wed, 2011-11-09 at 10:42 -0500, Tom Lane wrote:
> Nils Philippsen <nils at redhat.com> writes:
> > On Fri, 2011-11-04 at 13:12 -0400, Tom Lane wrote:
> >> I plan to provide the 1.2.x libpng shared library (and only the library,
> >> not its devel support files) in a libpng-compat subpackage for the time
> >> being.
> 
> > Any reason why the compat package ships the libpng-1.2.pc pkg-config
> > file?
> 
> Yeah: I tried it without first, and found that I couldn't rebuild
> anything.  There are boatloads of packages that have pkgconfig(libpng12)
> as an RPM-visible dependency, so if the compat package doesn't supply
> it, those packages won't install and you can't rebuild any of their
> dependencies.  I have no idea why it was considered a good thing for RPM
> to track this type of dependency, but it does.

Yuck :-/.

> > This made one of my packages use 1.5 headers, then later on
> > attempt to link to libpng12.so which failed.
> 
> I doubt that's coming from the libpng12 pkgconfig; more likely, you have
> some other package you're depending on that needs to be rebuilt first,
> because its pkgconfig file currently says to use -lpng12 in link commands.

Not really, I should have described it in more detail: the package
specifically asked pkg-config for libpng12 -- and since it exists, it
went building happily (with the 1.5 headers, from -devel) and only
failed when trying to link -lpng12. I'd have liked it to fail early
on ;-).

Nils
-- 
Nils Philippsen      "Those who would give up Essential Liberty to purchase 
Red Hat               a little Temporary Safety, deserve neither Liberty
nils at redhat.com       nor Safety."  --  Benjamin Franklin, 1759
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