[cairo] cairo built against libpng16

[Ingmar Runge]

On Tue, Apr 16, 2013 at 12:06 PM, Chris Wilson <chris at chris-wilson.co.uk> wrote:
> The advice from the png authors is that set_read_transform_info is even
> more dangerous than set_read_transform_fn.
>
> "The git head of libpng16 (and libpng17) has a fix that should allow user
> transforms (but not png_set_user_transform_info) to be called after
> png_read_update_info." - John Bowler

Sounds reasonable to me since there's no way to call
png_set_user_transform_info with the user data (pointer) only, you
always have to pass the depth and channels arguments too. They should
just add the ARGB32 and RGB24 conversions as built-in transforms while
they are at it, hehe. ;-) Is there a public libpng git repository by
the way? The one on sourceforge shows only "synched from tarball"
commits.