Bug#810003: gdk-pixbuf: Please upload a build against libpng16 to experimental

[Tobias Frost]

Am Dienstag, den 05.01.2016, 19:22 +0100 schrieb Andreas Henriksson:
> Hello Tobias Frost.
> 
> On Tue, Jan 05, 2016 at 12:33:37PM +0100, Tobias Frost wrote:
> > Source: gdk-pixbuf
> > Severity: wishlist
> > 
> > Hi,
> > 
> > as a few packages have a dependency on libpng and on gdk-pixbuf it
> > would be
> > nice if you could upload a package built against libpng16 to
> > experimental so
> > that people can easier test their changes.
> 
> If I understand this correctly all that should be required is a
> simple
> rebuild of gdk-pixbuf in an environment which provides the suitable
> libpng version, as gdk-pixbuf already depends on libpng-dev (|
> libpng12-dev).

Yes, a rebuild is enough

> An upload to experimental would have to temporarily change the
> dependency
> to something like libpng-dev (>= 1.6) | libpng16-dev, since
> satisfying
> from unstable is prefered over experimental but we explicitly want
> the experimental version.

libpng-dev is a virtual package, so Versioning won't work. 
I'd suggest for the experimental package to have a hard B-D on
libpng16-dev

> Once the transition goes live for real and libpng1.6 is uploaded to
> unstable a binNMU of gdk-pixbuf should make it pick up the newer
> version
> without any changes from the current state.

Later, the Depends: of libgdk-pixbuf2.0-dev needs also an update to
libpng-dev.
(Again, for the experimental package I'd hardcode libpng16-dev to be
extra sure that it will pick up the right version; there might be other
libs in some package B-D's,  insisting on libpng12-dev, so its better
if it bails out loud then)

> > 
> > (If you do not find time for this, I offer to do this via an NMU,
> > but only if
> > you give me the GO explicitly)
> 
> If my above understanding of only temporary changes needed is
> correct,
> please do feel free to NMU to experimental.

This will be a "throw-away" package, there should be no need to retain
those changes. 

> If there are any changes you want preserved, please post a patch to
> this bug report and I'll try to make sure it gets committed to
> pkg-gnome svn. (You can also quickly reach people via #debian-gnome
> on irc.debian.org.)

Will do!
Many thanks for your quick answer!

> > 
> > Many thanks!
> 
> Thanks for your time working on the libpng transition.
> 
> Regards,
> Andreas Henriksson


This is the patch I'd plan to use for the experimental package:

diff -Naur gdk-pixbuf-2.32.3_bak/debian/changelog gdk-pixbuf-
2.32.3/debian/changelog
--- gdk-pixbuf-2.32.3_bak/debian/changelog      2015-12-15
17:53:42.000000000 +0100
+++ gdk-pixbuf-2.32.3/debian/changelog  2016-01-05 22:11:13.313101882
+0100
@@ -1,3 +1,11 @@
+gdk-pixbuf (2.32.3-1.1) experimental; urgency=medium
+
+  * Non-maintainer upload.
+  * Upload to experimental: Rebuild against libpng16 to aid in the
+    transition. (see #800003)
+
+ -- Tobias Frost <tobi at debian.org>  Tue, 05 Jan 2016 21:59:04 +0100
+
 gdk-pixbuf (2.32.3-1) unstable; urgency=medium
 
   * New upstream release.
diff -Naur gdk-pixbuf-2.32.3_bak/debian/control gdk-pixbuf-
2.32.3/debian/control
--- gdk-pixbuf-2.32.3_bak/debian/control        2015-12-15
17:55:01.000000000 +0100
+++ gdk-pixbuf-2.32.3/debian/control    2016-01-05 21:58:58.516695873
+0100
@@ -14,7 +14,7 @@
                gnome-pkg-tools (>= 0.10),
                libglib2.0-dev (>= 2.37.6),
                libx11-dev,
-               libpng-dev | libpng12-dev,
+               libpng16-dev,
                libjpeg-dev,
                libtiff-dev,
                gobject-introspection (>= 0.9.12-4~),
@@ -73,7 +73,7 @@
          gir1.2-gdkpixbuf-2.0 (= ${binary:Version}),
          libglib2.0-dev (>= 2.37.6),
          libx11-dev,
-         libpng12-dev,
+         libpng16-dev,
          shared-mime-info
 Description: GDK Pixbuf library (development files)
  The GDK Pixbuf library provides:

-- 
tobi