Re: png Error while linking gui

[Fred Kiefer]

On 20.02.2013 19:45, Sebastian Reitenbach wrote:
> On Wednesday, February 20, 2013 18:36 CET, Riccardo Mottola 
> <riccardo.mottola@libero.it> wrote:
>
> > Hi,
> >
> > I upgraded libpng on NetBSD and now I cannot link gui anymore::
> >
> > Making all for tool set_show_service...
> >    Compiling file set_show_service.m ...
> >    Linking tool set_show_service ...
> > ../Source/./obj/libgnustep-gui.so: undefined reference to `png_sizeof'
> > gmake[4]: *** [obj/set_show_service] Error 1
>
> I guess when compiling NSBitmapImageRep+PNG.m, you got a warning about
> implicit declaration of function png_sizeof?
>
> > I have:
> > png-1.6.0nb1        Library for manipulating PNG images
> >
> > looks as if the function was removed ? is anybody using this version of
> > libpng?
> OpenBSD ships 1.5.10.
>
> The following API are now DEPRECATED:
>     png_info_init_3()
>     png_convert_to_rfc1123() which has been replaced
>       with png_convert_to_rfc1123_buffer()
>     png_data_freer()
>     png_malloc_default()
>     png_free_default()
>     png_reset_zstream()
>
> The following has been removed:
>     png_get_io_chunk_name(), which has been replaced
>       with png_get_io_chunk_type().  The new
>       function returns a 32-bit integer instead of
>       a string.
>     The png_sizeof(), png_strlen(), png_memcpy(), png_memcmp(), and
>       png_memset() macros are no longer used in the libpng sources and
>       have been removed.  These had already been made invisible to
> applications
>       (i.e., defined in the private pngpriv.h header file) since
> libpng-1.5.0.
>
> The signatures of many exported functions were changed, such that
>     png_structp became png_structrp or png_const_structrp
>     png_infop became png_inforp or png_const_inforp
> where "rp" indicates a "restricted pointer".
>
> here I see that png_sizeof() is just a #define to sizeof()
>
> so exchanging it with sizeof should just work?

Using sizeof() instead of png_sizeof() should work around that specific 
issue, but I read through the PNG webpage and there are a lot more 
changes coming:

http://www.libpng.org/pub/png/src/libpng-1.4.x-to-1.5.x-summary.txt

And even 1.5 is outdated by now, they have released 1.6 and are working 
on 1.7. In 1.6 they deprecated png_info_init_3() which means that we 
need to rewrite the whole png code. We rather should do that change at 
once. My 1.2.49 version of libpng already has png_create_info_struct(). 
Are there any older versions still in use that miss that function?