p5-tk: nonfunctional bindings with libpng

[mojca (Mojca Miklavec)]

Perl/Tk is not displaying PNG images as expected. I always wondered where the problem was and now I figured out that during installation of p5-tk the following errors/warnings are being thrown:

Writing MYMETA.yml and MYMETA.json
Test Compile/Run config/has_png.c
Using system's -lpng
Finding dependencies for PNG.xs
Finding dependencies for imgPNG.c
Invalid term: -32768 && INT_MAX == 32767 at /path/to/p5.16-tk/work/Tk-804.032/Tk/MakeDepend.pm line 55, </opt/local/include/libpng16/pngconf.h> line 508.
trailing:  -32768 && INT_MAX == 32767 at /path/to/p5.16-tk/work/Tk-804.032/Tk/MakeDepend.pm line 104, </opt/local/include/libpng16/pngconf.h> line 508.
ignore 'error "libpng requires a signed 16 bit type"'
ignore 'error "libpng requires an unsigned 16 bit type"'
Invalid term: -2147483646 && INT_MAX > 2147483646 at /path/to/p5.16-tk/work/Tk-804.032/Tk/MakeDepend.pm line 55, </opt/local/include/libpng16/pngconf.h> line 524.
trailing:  -2147483646 && INT_MAX > 2147483646 at /path/to/p5.16-tk/work/Tk-804.032/Tk/MakeDepend.pm line 104, </opt/local/include/libpng16/pngconf.h> line 524.
Invalid term: -2147483646 && LONG_MAX > 2147483646 at /path/to/p5.16-tk/work/Tk-804.032/Tk/MakeDepend.pm line 55, </opt/local/include/libpng16/pngconf.h> line 526.
trailing:  -2147483646 && LONG_MAX > 2147483646 at /path/to/p5.16-tk/work/Tk-804.032/Tk/MakeDepend.pm line 104, </opt/local/include/libpng16/pngconf.h> line 526.
ignore 'error "libpng requires a signed 32 bit (or more) type"'
ignore 'error "libpng requires an unsigned 32 bit (or more) type"'
Writing Makefile for Tk::PNG
Writing MYMETA.yml and MYMETA.json

[ryandesign (Ryan Schmidt)]

I see that too, but the p5-tk portfile isn't doing anything special, so this must be a defect in the p5-tk software; you should report the problem to its developers.

[mojca (Mojca Miklavec)]

Yes, that's an upstream bug, but there would be higher chances to fix it if we could come up with some basic diagnosis and a simple patch. If the main developer works on linux, the bug might remain open forever ;)

Here are the bug reports: ​https://rt.cpan.org/Public/Dist/Display.html?Name=Tk

[chrstphrchvz (Christopher Chavez)]

screenshot of photo.t (PNG results highlighted)

[chrstphrchvz (Christopher Chavez)]

Possibly related upstream ticket (closed before this ticket was opened): ​https://rt.cpan.org/Ticket/Display.html?id=87016

I can reproduce the errors/warnings above; to me that output suggests there is a bug in Tk::MakeDepend preventing it from parsing pngconf.h (from libpng).

So far I've only tried displaying PNGs by running the t/photo.t test, and some of the PNG results seem brightened/more white than expected (see screenshot below). But this occurs on Linux and Windows as well.

[chrstphrchvz (Christopher Chavez)]

Possibly related upstream ticket (closed before this ticket was opened): ​https://rt.cpan.org/Ticket/Display.html?id=87016

I can reproduce the errors/warnings above; to me that output suggests there is a bug in Tk::MakeDepend preventing it from parsing pngconf.h (from libpng).

I've opened a ticket upstream specifically regarding that output: ​https://rt.cpan.org/Ticket/Display.html?id=127612

[chrstphrchvz (Christopher Chavez)]

I finally opened an upstream ticket for the issue I observed in the demo: ​https://rt.cpan.org/Ticket/Display.html?id=129472. In that specific example, the problem appears to be in the conversion to PNG rather than the displaying of the finished PNG.

I think the scope of this ticket is has unintentionally become too broad; I'm not sure if I understood what the original issue is or if it's addressed already. The original issue I would think is "Perl/Tk is not displaying PNG images as expected", but what program/example was this observed in, i.e. how can it be reproduced? (Admittedly I have not tried very hard finding another PNG example program nor recreating one on my own.) But the MakeDepend.pm errors/warnings during installation and what I observe in the screenshot of one of the tests might both be separate issues.

[mojca (Mojca Miklavec)]

I wanted to say that you can try to fetch and extract ​http://mirror.ctan.org/systems/texlive/tlnet/install-tl-unx.tar.gz and run

./install-tl --gui perltk

and don't see the image. But then I ran this now and apparently something must have been fixed in the meantime since the time when I opened this ticket, as I see the image now (10.13, perl 5.28). On 10.7 and whatever perl version I had installed at that time I did not get the image displayed at all.