[pkg-wine-party] Bug#823991: Bug#823991: libpng16-16: generates a ton of noisy warnings

[Austin English]

On Wed, May 11, 2016 at 3:47 AM, Tobias Frost <tobi at debian.org> wrote:
> Package: libpng16-16
> Followup-For: Bug #823991
>
> Hi Daniel,
>
> can you provide more information, like the package version of your installed
> wine?  Did you mix stable and other suites? What are the libpng pacakges you
> have installed?
>
> (We have binNMUed everything depending on libpng12 so it is strange that your
> wine thinks it is compiled against libpng12)
>
> libpng has this version warning for a reason, as until version 1.4 it was possible to
> directly access struct members, therefore if those structs changed this *could*
> cause incompatiblities. The newer API forbids that, so this should be safe.
>
> However, taking a (very) short glimpse at the wine packages: Maybe I missed it
> but it seems from there that they do not declare a Depends on the libpng
> library package.
> That could be an explanation why it has not been binNMUed, and this would be
> actually a bug in wine (policy 3.5)
>
> CC'ing wine maintainers, maybe they can tell ...
>
>
> --
> tobi
>
>
>
> -- System Information:
> Debian Release: stretch/sid
>   APT prefers unstable-debug
>   APT policy: (500, 'unstable-debug'), (500, 'unstable'), (500, 'testing')
> Architecture: amd64 (x86_64)
> Foreign Architectures: i386
>
> Kernel: Linux 4.5.0-2-amd64 (SMP w/4 CPU cores)
> Locale: LANG=de_DE.UTF-8, LC_CTYPE=de_DE.UTF-8 (charmap=UTF-8)
> Shell: /bin/sh linked to /bin/dash
> Init: systemd (via /run/systemd/system)
>
> Versions of packages libpng16-16 depends on:
> ii  libc6   2.22-7
> ii  zlib1g  1:1.2.8.dfsg-2+b1
>
> libpng16-16 recommends no packages.
>
> libpng16-16 suggests no packages.
>
> -- no debconf information
>
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I didn't check Debian package, but upstream definitely uses libpng.
>From configure.ac:
dnl **** Check for libpng ****
if test "x$with_png" != "xno"
then
    WINE_PACKAGE_FLAGS(PNG,[libpng],,[$X_CFLAGS],[$X_LIBS],
        [AC_CHECK_HEADERS([png.h])
        if test "$ac_cv_header_png_h" = "yes"
        then
            WINE_CHECK_SONAME(png,png_create_read_struct,
                [AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#include
<png.h>]],[[typeof(png_set_expand_gray_1_2_4_to_8) *p]])],

[AC_DEFINE(HAVE_PNG_SET_EXPAND_GRAY_1_2_4_TO_8,1,[Define to 1 if
libpng has the png_set_expand_gray_1_2_4_to_8 function.])])],
                [PNG_CFLAGS=""],[$PNG_LIBS -lm -lz],[[libpng[[0-9]]*]])
        else
            PNG_CFLAGS=""
        fi])
fi
WINE_WARNING_WITH(png,[test "x$ac_cv_lib_soname_png" = "x"],
                 [libpng ${notice_platform}development files not
found, PNG won't be supported.])

https://source.winehq.org/git/wine.git/blob/HEAD:/configure.ac#l1590

-- 
-Austin